🚀 go-pugleaf

In article <ben.2630@epmooch.UUCP> ben@epmooch.UUCP (Rev. Ben A. Mesander) 
writes:
> If memory serves me right, the old Commodore PET machines could be
> physically damaged (ie smoke) by poking the wrong value into the wrong
> memory location. Good design...

Yep.  Way back in 1982, I bought a Comodore SuperPet (6809 AND 6502 CPUs, 
switch selectable, two operating systems, ran FORTRAN, BASIC in two flavors, APL and Pascal.  COBOL was promised, but never delivered).  Also got two SSDS drives, 330 baud modemand EPSON MX-80 printer, all for ONLY $5200... Gosh, it seemed like a good deal back then,with a full 128 K of banked memory).

Anyway, I was running a game called "FROG" which ran great on the older 
PETs.  It included a poke into some system location.  When I ran it the first time, the display went down to about 1 inch, and there was a LOUD squeal fron the case, accompanied by a piquant smell.  

Even after a immediate reboot, my IEEE-488 port would only talk to the 
disk drives, not themodem.  After replacing the board itself (under warranty), I still got "TIME_OUTS" from my comm program when trying to do file transfers.  Eventually, they had to replace the entire 
unit.  

I would have been happy to only have reformatted by floppys!!


David A. Cook

-----------------------------------------------
This disclamer intentianally left blank
-----------------------------------------------

dc...@cssun.tamu.edu (David A. Cook) writes:

>In article <ben.2630@epmooch.UUCP> ben@epmooch.UUCP (Rev. Ben A. Mesander) 
>writes:
>> If memory serves me right, the old Commodore PET machines could be
>> physically damaged (ie smoke) by poking the wrong value into the wrong
>> memory location. Good design...

Didn't there use to be a machine intrsuction that caused this problem?
Some wag gave it the mnemonic HCF ... Halt and Catch Fire!

------------------------------------------------------------
Dave Gurr			..!ukc!pyrltd!scol!davidgu
Santa Cruz Operation Ltd.

Disclaimer: All opinions expressed are those of the author's
cat, not necessarily those of the author, and certainly NOT
those of SCO Ltd. Miaouw.
------------------------------------------------------------

In article <ben.2630@epmooch.UUCP>, ben@epmooch.UUCP (Rev. Ben A. Mesander) writes:
> If memory serves me right, the old Commodore PET machines could be
> physically damaged (ie smoke) by poking the wrong value into the wrong
> memory location. Good design...
The original PC could control the voltage going to the monitor, I've
heard, with similar results..
-- 
Matti Nyk{nen			CS Student at Helsinki U, Finland
Trepanation!			email: mnyk...@cc.helsinki.fi

In article <1713@cygnus.scol.UUCP>, davidgu@scol.UUCP (David Gurr) writes:
> dc...@cssun.tamu.edu (David A. Cook) writes:
> 
> >In article <ben.2630@epmooch.UUCP> ben@epmooch.UUCP (Rev. Ben A. Mesander) 
> >writes:
> >> If memory serves me right, the old Commodore PET machines could be
> >> physically damaged (ie smoke) by poking the wrong value into the wrong
> >> memory location. Good design...
> 
> Didn't there use to be a machine intrsuction that caused this problem?
> Some wag gave it the mnemonic HCF ... Halt and Catch Fire!


Okay, this is bound to kick off a thread that was done to
death a while ago. So what do I do? I participate! :-)

Here's one list of these things...


				- peterd

------------------------------------------------------------


      MNEMONIC		          INSTRUCTION
     ----------                  -------------

			-A-

	AAC			Alter All Commands
	AAD                     Alter All Data
	AAO                     Add And Overflow
	AAR			Alter at Random
	AB			Add Backwards
	ABC			AlphaBetize Code
 	ABR                     Add Beyond Range
        ACC                     Advance CPU clock
	ACDC			Allow Controller to die peacefully
	ACQT                    Advance Clock to Quitting Time
	ADB                     Another Damn Bug [UNIX]
        AEE                     Absolve engineering errors
	AFF                     Add Fudge Factor
	AFHB                    Align Fullword on Halfword Boundary
	AFP                     Abnormalize Floating Point
	AFR			Abort Funny Routine
	AFVC			Add Finagle's Variable Constant
	AGB                     Add GarBage
	AI  			Add Improper(ly)
	AIB			Attack Innocent Bystander
	AMM                     Answer My Mail
	AMM			Add Mayo and Mustard
	AMS			Add Memory to System
	ANFSCD			And Now For Something Completely Different
	AOI			Annoy Operator Immediate
	AR 			Advance Rudely
	AR 			Alter Reality
	ARN			Add and Reset to Nonzero
	ARZ			Add and Reset to Zero
	AS			Add Sideways
	AT			Accumulate Trivia
	AWP			Argue With Programmer
	AWTT			Assemble with Tinker Toys
			-B-
	BA			Branch Anywhere
	BAC			Branch to Alpha Centauri
	BAF			Blow all Fuses
	BAFL			Branch and Flush
	BAH			Branch and Hang
	BALC			Branch and Link Cheeseburger
	BAP			Branch and Punt
	BAW			Bells and Whistles
        BB                      Branch on bug
	BBBB			Byte Baudy Bit and Branch
	BBD			Branch on Bastille Day
	BBIL			Branch on Burned-Out Indicator Light
	BBLB			Branch on Blinking Light Bulb
	BBT			Branch on Binary Tree
	BBW			Branch Both Ways
	BCB			Burp and Clear Bytes
        BCF		        Branch and Catch Fire
	BCF			Branch on Chip box Full
	BCIL			Branch Creating Infinite Loop
	BCR			Backspace Card Reader
	BCU			Be Cruel and Unusual
	BD			Backspace Disk
	BD			Branch to Data
	BDC			Break Down and Cry
	BDI			Branch to Data, Indirect
	BDM			Branch and Disconnect Memory
	BDT			Burn Data Tree
	BE                      Branch Everywhere
	BEW			Branch Either Way
	BF			Belch Fire
	BFF			Branch and Form Feed
	BFM			Be Fruitful and Multiply
	BH			Branch and Hang
	BIR                     Branch Inside Ranch
        BIRM                    Branch on index register missing
	BLC			Branch and Loop Continuous
	BLI			Branch and Loop Infinite
	BLM			Branch, Like, Maybe
	BLMWM			Branch, Like, Maybe, Wow, Man
	BLP			Boot from Line Printer
	BLR			Branch and Lose Return
	BLSH			Buy Low, Sell High
	BM			Branch Maybe
	BMI			Branch on Missing Index
	BMI			Branch to Muncee, Immediate
	BMP			Branch and Make Popcorn
	BMR			Branch Multiple Registers
	BNA			Branch to Nonexistant Address
	BNCB			Branch and Never Come Back
	BNR			Branch for No Reason
	BOB			Branch on Bug
	BOD			Beat on the Disk
	BOD			Branch on Operator Desperate
	BOH			Branch on Humidity
        BOHP                    Bribe operator for higher priority
	BOI			Byte Operator Immediately
	BOP			Boot OPerator
	BOT			Branch On Tree
	BPB			Branch on Program Bug
	BPDI			Be Polite, Don't Interrupt
	BPIM			Bury Programmer in Manuals
	BPL			Branch PLease
	BPO			Branch on Power Off
	BPP			Branch & Pull Plug
	BR			Byte and Run
	BRA			Branch to Random Address
	BRI			Branch Indefiniteley
	BRO			BRanch to Oblivion
	BRSS			Branch on Sunspot
	BS			Behave Strangely
	BSC			Branch on Second Coming
	BSI			Backup Sewer Immediately
	BSM			Branch and Scramble Memory
        BSO                     Branch on sleepy operator
	BSP			Backspace Punch
	BSR			Branch and Stomp Registers
	BSST			BackSpace and Stretch Tape
	BST			Backspace and Stretch Tape
	BTD			Byte The Dust
	BTD			Branch on Time of Day
	BTJ			Branch and Turn Japanese
	BTO			Branch To Oblivion
	BTW			Branch on Third Wednesday
	BU			Branch Unexpectedly
	BVS			Branch & Veer South
	BW			Branch on Whim
	BWABL			Bells, Whistles, and Blinking Lights
	BWC			Branch When Convenient
	BWF			Busy - Wait Forever
	BWOP			BeWilder OPerator
	BYDS			Beware Your Dark Side
	BYTE			BYte TEst
			-C-
	CAC                     Calling All Cars...
	CAC			Cash And Carry
	CAF			Convert ASCII to Farsii
	CAI			Corrupt Accounting Information
	CAIL			Crash After I Leave
	CAR			Cancel Accounts Receivable
	CAT			Confused And Tired [UNIX]
	CB			Consult Bozo
	CBA			Compare and Branch Anyway
	CBBR			Crash & Blow Boot ROM
	CBNC			Close, but no Cigar
	CBS			Clobber BootStrap
	CC			Call Calvery
	CC			Compliment Core
	CCB			Chocolate Chip Byte-mode
	CCB			Consult Crystal Ball
	CCC			Crash if Carry Clear
	CCCP			Conditionally Corrupt Current Process
        CCD                     Clear Core and Dump
	CCD			Choke Cough and Die
	CCR			Change Channels at Random
	CCS			Chinese Character Set
	CCWR			Change Color of Write Ring
	CD			Complement Disk
	CDC			Close Disk Cover
	CDC			Clear Disk and Crash
  	CDIOOAZ			Calm Down, It's Only Ones and Zeroes
	CDS			Change Disk Speed
	CEMU			Close Eyes and Monkey With User Space
	CEX			Call EXterminator
	CF			Come From (replaces GOTO)
	CFE			Call Field Engineer
	CFP			Change and Forget Password
	CFS			Corrupt File Structure
	CG			Convert to Garbage
	CH			Create Havoc
	CHAPMR			Chase Pointers Around Machine Room
	CHCJ			Compare Haig to Christine Jorgensen
	CHSE			Compare Half-words and Swap if Equal
	CIB			Change Important Byte
	CIC			Cash In Chips
	CID			Compare and Ignore Data
	CIMM			Create Imaginary Memory Map
	CIZ			Clear If Zero
	CLBR			Clobber Register
	CLBRI			Clobber Register Immediately
	CM			Circulate Memory
	CMD			Compare Meaningless Data
	CMD			CPU Melt Down
	CMI			Clobber Monitor Immediately
	CML			Compute Meaning of Life
	CMP			Create Memory Prosthesis
	CMS			Click MicroSwitch
	CN			Compare Nonsensically
	CNB			Cause Nervous Breakdown
	CNS			Call Nonexistent Subroutine
	COD			Crash On Demand
	COLB			Crash for Operator's Lunch Break
	COCS			Copy Object Code to Source
	COM			Clear Operator's Mind
	COMF			COMe From
	CON			Call Operator Now
	COS			Copy Object code to Source file
	COWYHU			Come Out With Your Hands Up
	CP 			Compliment Programmer
	CP%FKM			CPU - FlaKeout Mode
	CP%WM			CPU - Weird Mode
	CPB			Create Program Bug
	CPN			Call Programmer Names
	CPPR			Crumple Printer Paper and Rip
	CRASH			Continue Running After Stop or Halt
	CRB			Crash and Burn
	CRD			Confirm Rumor by Denial
	CRM			Clear Random Memory
	CRM			CReate Memory
	CRN			Convert to Roman Numerals
	CRN			Compare with Random Number
	CRYPT			reCuRsive encrYPt Tape mneumonic [UNIX]
	CS			Crash System
	CSL			Curse and Swear Loudly
	CSN			Call Supervisor Names
	CSNIO			Crash System on Next I/O
	CSS			Crash Subsidiary Systems
	CSU			Call Self Unconditional
	CTDMR			Change Tape Density, Mid Record	
	CTT			Call Time & Temperature
	CU			Convert to Unary
	CUC			Cheat Until Caught
	CVFL			ConVert Floating to Logical
	CVFP			ConVert FORTRAN to PASCAL
	CVG			Convert to Garbage
	CWAH			Create Woman and Hold
	CWB			Carry With Borrow
	CWDC			Cut Wires and Drop Core
	CWG			Chase Wild Goose
	CWGK			Compare Watt to Genghis Khan
	CWIT			Compare Watt to Ivan the Terrible
	CWM			Compare Watt to Mussolini
	CWOM			Complement Write-only Memory
	CZZC			Convert Zone to Zip Code
			-D-
	DA			Develop Amnesia
	DAB			Delete All Bugs
	DAO			Divide And Overflow
	DAP			De-select Active Peripheral
	DAUF			Delete All Useless Files
	DB			Drop Bits
	DBL			Desegregate Bus Lines
	DBR			Debase Register
	DBTP			Drop Back Ten and Punt
	DBZ			Divide by Zero
	DC			Divide and Conquer
	DC			Degauss Core
	DCAD			Dump Core And Die
	DCD			Drop Cards Double
	DCGC			Dump Confusing Garbage to Console
	DCI			Disk Crash Immediate
	DCON			Disable CONsle
	DCR			Double precision CRash
	DCT			Drop Cards Triple
	DCWPDGD			Drink Coffee, Write Program, Debug, Get Drunk
	DD			Destroy Disk
	DD 			Drop Disk
	DDC			Dally During Calculations
	DDOA			Drop Dead On Answer
	DDS			Delaminate Disk Surface
	DDWB			Deposit Directly in Wastepaper Basket
	DE			Destroy Peripherals
	DEB			Disk Eject Both
	DEC			Decompile Executable Code
	DEI			Disk Eject Immediate
	DEM			Disk Eject Memory
	DGT			Dispense Gin & Tonic
	DHTPL			Disk Head Three Point Landing
	DIA			Develop Ineffective Address
	DIE			DIsable Everything
	DIIL			Disable Interrupts and enter Infinite Loop
	DIRFO			Do It Right For Once
	DISC			DISmount Cpu
	DK			Destroy Klingons
	DK%WMM			Disk Unit - Washing Machine Mode
	DKP			Disavow Knowledge of Programmer
	DLN			Don't Look Now...
	DLP			Drain Literal Pool
	DMAG			Do MAGic
	DMNS			Do What I Mean, Not What I Say
	DMPE			Decide to Major in Phys. Ed.
	DMPK			Destroy Memory Protect Key
	DMZ			Divide Memory by Zero
	DNPG			Do Not Pass Go
	DO			Divide and Overflow
	DOC			Drive Operator Crazy
	DPCS			Decrement Program Counter Secretly
	DPMI			Declare Programmer Mentally Incompetent
	DPN			Double Precision No-op
	DPR			Destroy Program
	DPS			Disable Power Supply
	DR			Detach Root
	DRAF			DRAw Flowchart
	DRAM			Decrement RAM
	DRD			DRop Dead
	DRI			Disable Random Interrupt
	DROM			Destroy ROM
	DRT			Disconnect Random Terminal
	DS			Deadlock System
	DSI			Do Something Interesting
	DSO			Disable System Operator
	DSP			Degrade System Performance
	DSR			Detonate Status Register
	DSTD			Do Something Totally Different
	DSUIT			Do Something Utterly, Indescribably Terrible
	DT%FFP			DecTape - unload and Flappa FlaP
	DT%SHO			DecTape - Spin Hubs Opposite
	DTB			Destructively Test Bit
	DTC			Destroy This Command
	DTE			Decrement Telephone Extension
	DTI			Do The Impossible
	DTRT			Do The Right Thing
	DTVFL			Destroy Third Variable From Left
	DU			Dump User
	DUD			Do Until Dead
	DW			Destroy World
	DWIM			Do What I Mean
	DWIT			Do What I'm Thinking
			-E-
	EA			Enable Anything
	EAC			Emulate Acoustic Coupler
	EAL			Enable AC to Logic rack
	EAO			Enable AC to Operator
	EBB			Edit and Blank Buffer
	EBB			Empty Bit Bucket
	EBR			Erase Before Reading
	EBRS			Emit Burnt Resistor Smell
        EC                      Eat card
	ECL			Early Care Lace
	ECO			Electrocute Computer Operator
	ECP			Erase Card Punch
	ED			Eject Disk
	ED			Execute Data (verrrry useful)
	EDD			Eat Disk and Die
	EDIT			Erase Data and Increment Time
	EDP			Emulate Debugged Program
	EDR			Execute Destructive Read
	EDS			Execute Data Segment
	EEOIFNO			Execute Every Other Instruction From
				   Now On
	EEP			Erase Entire Program
	EFB			Emulate Five-volt Battery
	EFD			Emulate Frisbee Using Disk Pack
	EFD			Eject Floppy Disk
	EFE			Emulate Fatal Error
	EHC			Emulate Headless Chicken
	EIAO			Execute In Any Order
	EIO			Erase I/O page
	EIOC			Execute Invalid Op-code
	EIP			Execute Programmer Immeditely
	EJD%V			EJect Disk with initial velocity V
	ELP			Enter Loop Permenantly
        EM                      Emulate 407
	EM			Evacuate Memory
	EMM			Emulate More Memory
	EMPC			Emulate Pocket Calculator
	EMSE			Edit and Mark Something Else
	EMSL			Entire Memory Shift Left
	EMT			Electrocute Maintenance Technician
        EMW                     Emulate Matag washer
	ENA			ENable Anything
	ENF			Emit Noxious Fumes
	ENO			Emulate No-Op
	EO			Electrocute Operator
	EOB			Execute Operator and Branch
	EOI			Explode On Interrupt
	EOS			Erase Operating System
	EP			Execute Programmer
	EPI			Execute Programmer Immediately
	EPITS			Execute Previous Instruction Then Skip
	EPL			Emulate Phone Line
	EPP			Eject Printer Paper
	EPS			Electrostatic Print and Smear
	EPS			Execute Program Sideways
	EPSW			Execute Program Status Word
	EPT			Erase Process Table
	EPT			Erase Punched Tape
	ERIC			Eject Random Integrated Circuit
	ERM			Erase Reserved Memory
	EROM			Erase Read Only Memory
	EROS			Erase Read-only Storage
	ESB			Eject Selectric Ball
	ESC			Emulate System Crash
	ESD			Eject Spinning Dish
	ESD			Eat Shit & Die
	ESL			Exceed Speed of Light
	ESP			Enable SPrinkler system
	ETI			Execute This Instruction
	ETM			Emulate Trinary Machine
	EVC			Execute Verbal Commands
	EWD			Enter Warp Drive
	EWM			Enter Whimsy Mode
	EXI			Execute Invalid Operation
	EXOP			Execute Operator
	EXPP			Execute Political Prisoner
			-F-
	FAY			Fetch Amulet of Yendor
	FB			Find Bugs
	FC			Fry Console
	FCJ			Feed Cards and Jam
	FD			Forget Data
	FDR			Feed Disk Randomly
	FERA			Forms Eject and Run Away
	FFF			Form Feed Forever
	FLD			FLing Disk
	FLI			Flash Lights Impressively
	FM			Forget Memory
	FMP			Finish My Program
	FOPC			False Out-of-Paper Condition
	FPC			Feed Paper Continuously
	FPT			Fire Photon Torpedoes
	FRG			Fill with Random Garbage
	FS			Feign Sleep
	FSM			Fold, Spindle and Mutilate
	FSRA			Forms Skip and Run Away
			-G-
	GBB			Go to Back of Bus
	GCAR			Get Correct Answer Regardless
	GDP			Grin Defiantly at Programmer
	GDR			Grab Degree and Run
	GENT			GENerate Thesis
	GEW{JO}			Go to the End of the World {Jump Off}
	GFD			Go Forth and Divide
	GFM			Go Forth and Multiply
	GIE			Generate Irreversible Error
	GLC			Generate Lewd Comment
	GMC			Generate Machine Check
	GMCC			Generate Machine Check and Cash
	GND			Guess at Next Digit
	GORS			GO Real Slow
	GREM			Generate Random Error Message
	GREP			Global Ruin, Expiration, and Purgation [UNIX]
	GRMC			Generate Rubber Machine Check
	GS			Get Strange
	GSB			Gulp and Store Bytes
	GSI			Generate Spurious Interrupts
	GSU			Geometric Shift Up
	GTJ			Go To Jail
			-H-
	HACF			Halt And Catch Fire
	HAH			Halt And Hang
	HBW			Hang Bus & Wait
	HCP			Hide Central Processor
	HCRS			Hang in CRitical Section
	HDO			Halt and Disable Operator
	HDH			Hi Dee Ho
	HDRW			Halt and Display Random Word
	HELP			Type "No Help Available"
	HF			Hide File
	HGD			Halt, Get Drunk
	HHB			Halt and Hang Bus
	HIS			Halt in Imposible State
	HOO			Hide Operator's Output
	HRPR			Hang up and Ruin Printer Ribbon
	HSC			Halt on System Crash
	HSJ			Halt, Skip and Jump
	HTC			Halt & Toss Cookies
	HTS			Halt & Throw Sparks
	HUAL			Halt Until After Lunch
	HUP			Hang Up Phone
	HWP			Halt Without Provocation
			-I-
	IAND			Illogical AND
	IAE			Ignore All Exceptions
        IAI                     Inquire and ignore
	IBM			Increment and Branch to Muncee
	IBP			Insert Bug and Proceed
	IBR			Insert BUgs at Random
	ICB			Interrupt, Crash and Burn
	ICM			Immerse Central Memory
	ICMD			Initiate Core Melt Down
	ICSP			Invert CRT Screen Picture
	IDC			Initiate Destruct Command
	IDI			Invoke Divine Intervention
	IDNOP			InDirect No-OP
	IDPS			Ignore Disk Protect Switch
	IEOF			Ignore End Of File
	IF			Invoke Force
	IGI			Increment Grade Immediately
	IGIT			Increment Grade Immediately Twice
	IHC			Initiate Head Crash
	II			Inquire and Ignore
	IIB			Ignore Inquiry and Branch
	IIC			Insert Invisible Characters
	IIL			Irreversable Infinite Loop
	IM			Imagine Memory
	IMBP			Insert Mistake and Blame Programmer
	IMP                     Imitate Monty Python
	IMPG			IMPress Girlfriend
	IMV			IMpress Visitors
	INCAM			INCrement Arbitrary Memory
	INI			Ignore Next Instruction
	INOP			Indirect No-OP
	INR			INstigate Rumor
	INW			INvalidate Warranty
	IOI			Ignore Operator's Instruction
	IOR			Illogical OR
	IP			Increment and Pray
	IPI			Ignore Previous Instruction
	IPM 			Ignore Programmer's Mistakes
	IPOP			Interrupt Processor, Order Pizza
	IPS			Incinerate Power Supply
	IPS			Increment Power Supply
	IPT			Ignite Paper Tape
	IRB			Invert Record and Branch
	IRBI			Insert Random Bits Indexed
	IRC			Insert Random Commands
	IRE			Insert Random Errors
	IRI			Ignore Rude Interrupts
	IRPF			Infinite Recursive Page Fault
	ISC			Ignore System Crash
	ISC			Insert Sarcastic Comments
	ISC			Ignore Supervisor Calls
	ISI			Increment and Skip on Inifinity
	ISP			Increment and Skip on Pi
	ISTK			Invert STacK
	ITML			Initiate Termites into Macro Library
	IU			Ignore User(s)
	IZ			Ignore Zeroes
			-J-
	JAA			Jump Almost Always
	JBS			Jump and Blow Stack
	JCI			Jump to Current Instruction
	JFM			Jump on Full Moon
	JHRB			Jump to H&R Block
	JLP			Jump and Lose Pointer
	JMAT			JuMp on Alternate Thursdays
	JN			Jump to Nowhere
	JNL			Jump when programmer is Not Looking
	JOM			Jump Over Moon
	JOP			Jump OPerator
	JPA			Jump when Pizza Arrives
	JRAN			Jump RANdom
	JRCF			Jump Relative and Catch Fire
	JRGA			Jump Relative and Get Arrested
	JRL			Jump to Random Location
	JRSR			Jump to Random Subroutine
	JSC			Jump on System Crash
	JSU			Jump Self Unconditional
	JT			Jump if Tuesday
	JTT			Jump and Tangle Tape
	JTZ			Jump to Twilight Zone
	JWN			Jump When Necessary
			-K-
        KCE                     Kill Consultant on Error
	KEPITU			Kill Every Process In The Universe
	KP			Krunch Paper
	KSR			Keyboard Shift Right
	KUD			Kill User's Data
			-L-
	LAC			Lose All Communication
	LAGW			Load And Go Wrong
	LAP			Laugh At Program(mer)
	LCC			Load and Clear Core
	LCD			Launch Cartridge Disk
	LCK			Lock Console Keyswitch
	LEB			Link Edit Backwards
	LIA			Load Ineffective Address
	LMB			Lose Message and Branch
	LMO			Load and Mug Operator
	LMYB			Logical MaYBe
	LN			Lose inode Number [UNIX]
	LNP			Load N digits of Pi
	LOSM			Log Off System Manager
	LP%PAS			Line Printer - Print And Smear
	LP%RDD			Line Printer - Reverse Drum Direction
	LP%TCR			Line Printer - Tangle and Chew Ribbon
	LPA			Lead Programmer Astray
	LPRTC			Load Program counter from Real Time Clock
	LR                      Load Revolver
	LRA			Load RetroActively
	LRD			Load Random Data
        LSPSW                   Load and Scramble PSW
	LTS                     Link To Sputnik
	LUM			LUbricate Memory
	LWE			Load WhatEver
	LWM			Load Write-only Memory
			-M-
	MAB			Melt Address Bus
	MAN			Make Animal Noises
	MAZ			Multiply Answer by Zero
	MBC			Make Batch Confetti
	MBH			Memory Bank Hold-up
	MBR			Multiply and be Fruitful
	MBTD			Mount Beatles on Tape Drive
	MBTOL			Move Bug To Operator's Lunch
	MC			Move Continuous
	MD			Move Devious
	MDB			Move and Drop Bits
	MDC			Make Disk Crash
	MDDHAF			Make Disk Drive Hop Across Floor
	MFO			Mount Female Operator
	MLB			Memory Left shift and Branch
	MLP			Make Lousy Program
	MLP			Multiply and Lose Precision
	MLR			Move and Lose Record
	MMLG			Make Me Look Good
	MNI			Misread Next Instruction
	MOG			Make Operator Growl
	MOP			Modify Operator's Personality
	MOU			MOunt User [causes computer to screw you]
	MPLP			Make Pretty Light Pattern
	MRZ			Make Random Zap
	MSGD			Make Screen Go Dim
	MSP			Mistake Sign for Parity
	MSPI			Make Sure Plugged In
	MSR			Melt Special Register
        MST                     Mount Scotch Tape
	MT%HRDV			Mag Tape - High speed Rewind and Drop Vaccuum
	MTI			Make Tape Invalid
	MW			Malfunction Whenever
	MW			Multiply Work
	MWAG			Make Wild-Assed Guess
	MWC			Move and Wrap Core
	MWT			Malfunction Without Telling
			-N-
	NBC			Negate By Clearing
	NMI			Negate Most Integers
	NOP           		Needlessly Omit Pointer
	NPC			Normalize Program Counter
	NTGH			Not Tonight, i've Got a Headache
			-O-
	OCF			Open Circular File
	OMC			Obscene Message to Console
	OML			Obey Murphy's Laws
	OPP			Order Pizza for Programmer
	OSI			Overflow Stack Indefinitely
	OTL			Out To Lunch
			-P-
	P$*!			Punch Obscenity
	PA			Punch in ASCII
	PAS			Print And Smear
	PAUD			PAUse Dramatically
	PAZ			Pack Alpha Zone
	PBC			Print and Break Chain
	PBD			Print and Break Drum
	PBM			Pop Bubble Memory
	PBPBPBP			Place Backup in Plain Brown Paper Bag, Please
	PBST			Play Batch mode Star Trek
	PCI			Pleat Cards Immediate
	PCR			Print and Cut Ribbon
	PD			Play Dead
	PD			Punch Disk
	PDLD			Power Down and Lock Door (to computer room)
	PDSK			Punch DiSK
	PEHC			Punch Extra Holes in Cards
	PEP			Print on Edge of Paper
	PFD			Punt on Fourth Down
	PFE			Print Floating Eye [rogue]
	PFML			Print Four Million Lines
	PI			Punch Invalid
	PIBM			Pretend to be an IBM
	PIC			Print Illegible Characters
	PIC			Punch Invalid Character
        PLSC                    Perform Light Show on Console
	PNIH                    Place Needle in Haystack
	PNRP			Print Nasty Replies to Programmer
	PO			Punch Operator
	POCL			Punch Out Console Lights
	POG                     Print Only Greek
	POPI			Punch OPerator Immediately
	POPN			Punch OPerator's Nose
	PPA			Print Paper Airplanes
	PPL			Perform Perpetual Loop
	PPP			Print Programmer's Picture
	PPR			Play Punk Rock
        PPSW                    Pack Program Status Word
	PSP			Print and Shred Paper
	PSR			Print and Shred Ribbon
	PTP			Produce Toilet Paper
	PVLC			Punch Variable Length Card
	PWP			Print Without Paper
	PWS			create PoWer Surge
	PYS			Program Yourself
			-Q-
	QWYA			Quit While Your Ahead
			-R-
	RA			Randomize Answer
	RAM			Read Ambiguous Memory
	RAN			Random Opcode [similar to 16-bit what gate]
	RASC			Read And Shred Card
	RAST			Read And Shred Tape
	RAU			Ridicule All Users
	RBAO			Ring Bell and Annoy Operator
	RBG			Read Blank Tape
	RBLY			Restore Back-up from Last Year
        RBT                     Rewind and Break Tape
	RC			Rewind Core
	RCAJ			Read Card And Jam
	RCB			Read Command Backwards
	RCB			Run Clock Backwards
	RCC			Read Card and Chew
	RCCP			Randomly Corrupt Current Process
	RCF			Rewind Cabinet Fans
	RCKG			Read Count Key and Garbage
	RCL 			Rotate Carry Left
	RCR			Rewind Card Reader
	RCRV			Randomly Convert to Reverse Video
	RCSD			Read Card, Scramble Data
	RD			Reverse Directions
	RD			Randomize Data
	RDA			Refuse to Disclose Answer
	RDB			Run Disk Backwards
	RDB			Replace Database with Blanks
	RDD			Reverse Disk Drive
	RDDBF			Rock Disk Drive Back and Forth
	RDEB			Read and Drop Even number of Bits
	RDF			Randomize Directory Filenames
        RDI                     Reverse Drum Immediate
	RDR			Reverse Disk Rotation
	RDS			Read SiDeways
	RENVR			REName Variables Randomly
	RET			Read and Erase Tape
	RF			Read Fingerprints
	RG			Record Garbage
	RHO			Randomize and Halt if not = to 0
	RIC			Rotate Illogical thru Carry
	RID			Read Invalid Data
	RIOP			Rotate I/O Ports
	RIR			Read Invalid Record
	RIRG			Read Inter-record Gap
	RJE			Return Jump and Explode
	RLC			Relocate and Lose Core
	RLC			Reread Last Card
	RLC			Rotate Left with Carolyn
	RLI			Rotate Left Indefinitely
	RLP			Rewind Line Printer
	RLP			Refill Light Pen
	RM			Ruin My files
	RMI			Randomize Memory Immediate
	RMT			Remove Trap
	RMV			Remove Memory Virtues
	RN			Read Noise
	RNBS			Reflect Next Bus Signal
	ROC			Randomize Op Codes
	ROC			Rotate Outward from Center
	ROD			ROtate Diagonally
	ROM			Read Operator's Mind
	ROO			Rub Out Operator
	ROOP			Run Out Of Paper
	ROPF			Read Other People's Files
	ROS			Reject Operating System
	ROS			Return On Shield
	RP			Read Printer
	RPB			Read Print and Blush
	RPB			Raise Parity Bits
	RPBR			Reverse Parity and BRanch
	RPC			Rotate Program Counter
	RPM			Read Programmer's Mind
	RPU			Read character and Print Upsidedown
	RRC			Rotate Random thru Carry
	RRR			Read Record and Run away
	RRR			Randomly Rotate Register
	RRRL			Random Rotate Register Left
	RRRR			Random Rotate Register Right
	RRSGWSSNK		Round and Round She Goes, Where
				   She Stops, Nobody Knows
	RRT			Record and Rip Tape
	RS			Random Slew
	RSD			On Read Error Self-Destruct
	RST			Rewind and Stretch Tape
	RSTOM			Read From Store-only Memory
        RT                      Reduce Throughput
	RTS			Return To Sender
	RVAC			Return from VACation
	RWCR			ReWind Card Reader
	RWD			ReWind Disk
	RWF			Read Wrong File
			-S-
	SA			Store Anywhere
	SAD			Search(seek) and Destroy
	SAI			Skip All Instructions
	SAS			Sit And Spin
	SAS			Show Appendix Scar
	SBE			Swap Bits Erratically
	SC			Scramble Channels
	SC			Shred Cards
	SCB			Spindle Card and Belch
	SCCA			Short Circuit on Correct Answer
	SCD			Shuffle and Cut DEC
	SCH			Slit Cards Horizontal
	SCI			Shred Cards Immediate
	SCM			Set for Crash Mode
	SCOM			Set Cobol-Only Mode
	SCRRC			SCRamble Register Contents	
	SCST			Switch Channel to Star Trek
	SCTR			Stick Card To Reader
	SD			Scramble Directory
	SD			Slip Disk
	SDC			Spool Disk to Console
	SDD			Seek and Destroy Data
	SDDB			Snap Disk Drive Belt
	SDE			Solve Differential Equations
	SDI			Self Destruct Immediately
	SDM			Search and Destroy Memory
	SDR			Slam Down Rondo [worst soda ever made]
	SEB			Stop Eating and Burp
	SEOB			Set Every Other Bit
	SEX			Set EXecution register [real on the RCA 1802]
	SEX			Sign EXtend
	SFH			Set Flags to Half-mast
	SFP			Send for Pizza
	SFR			Send for Reinforcements
	SFT			Stall For Time
	SFTT			Strip Form Tractor Teeth
	SHAB			Shift a Bit
	SHABM			Shift a Bit More
	SHB			Stop and Hang Bus
	SHCD			SHuffle Card Deck
	SHIT			Stop Here If Thursday
	SHON			Simulate HONeywell CPU [permanent NO-OP]
	SHRC			SHRed Card
	SHRT			SHRed Tape
	SID			Switch to Infinite Density
        SIP                     Store Indefinite Precision
	SJV			Scramble Jump Vectors
	SLP			Sharpen Light Pen
	SMC			Scramble Memory Contents
	SMD			Spontaneous Memory Dump [classfied data only]
	SMR			Skip on Meaningless Result
	SMS			Shred Mylar Surface
	SNARF			System Normalize and Reset Flags
	SNM			Show No Mercy
	SNO			Send Nukes on Overflow
	SOAWP			SOlve All the World'd Problems
	SOB			Stew On Brew [a real PDP-11 instruction]
	SOD			Surrender Or Die !
	SOI                     Screw O'Coin Intentionally (personal one)
	SOP			Stop and Order Pizza
	SOS			Sign off, Stupid
	SOT			Sit on a Tack
	SP			Scatter Print
	SPA			Sliding Point Arithmetic
        SPD                     Spin Dry Disc
	SPB			Simulate Peanut Butter
	SPS			Set Panel Switches
	SPSW			Scramble Program Status Word
	SQPWYC			Sit Quietly and Play With Your Crayons
	SRBO			Set Random Bits to Ones
	SRBZ			Set Random Bits to Zeroes
	SRC			Select Random Channel
        SRCC                    Select Reader and Chew Cards
	SRD			Switch to Random Density
	SRDR			Shift to Right Double Ridiculous
	SRO			Sort with Random Ordering
	SROS			Store in Read Only Storage
	SRR			Shift Registers Random
	SRSD			Seek Record and Scratch Disk
	SRSZ			Seek Record and Scar Disk
	SRTC			Stop Real-Time Clock
	SRU			Signoff Random User
	SRZ			Subtract and Reset to Zero
	SRDR			Shift Right Double Ridiculous
	SRSD			Seek Record and Scar Disk
	SRZ			Subtract and Reset to Zero
	SSB			Scramble Status Byte
	SSJ			Select Stacker and Jam
	SSJP			Select Stacker and JumP
	SSM			Solve by Supernatural Means
	SSP			Seek SPindle
	SSP			Smoke and SPark
	SST			Seek and Stretch Tape
	ST			Set and Test
	STA			STore Anywhere
	STC			Slow To a Crawl
	STD			Stop, Take Drugs
	STM			STretch Magtape
	STM			Skip on Third Monday
	STO			Strangle Tape Operator
	STROM			Store in Read-only Memory
	STPR			SToP Rain
	STROM			STore in Read-Only Memory
	STTHB			Set Terminal to Three Hundred Baud
	SUIQ			Subtract User's IQ
	SUME			SUprise ME
	SUP			Solve Unsolvable Problem
	SUR			Screw Up Royally
	SUS			Stop Until Spring
	SUS			Subtract Until Senseless
	SWAT			SWAp Terminals
	SWN			SWap Nibbles
	SWOS			Store in Write Only Storage
	SWS			Sort to Wrong Slots
	SWT			Select Wrong Terminal
	SWU			Select Wrong Unit
	SWZN			Skip Whether Zero or Not
	SZD			Switch to Zero Density
			-T-
	TAH			Take A Hike
	TAI			Trap Absurd Inputs
	TARC			Take Arithmetic Review Course
	TBFTG			Two Burgers and Fries To Go
	TC			Transmit Colors (but avoid red)
	TDB			Transfer and Drop Bits
	TDRB			Test and Destroy Random Bits
	TDS			Trash Data Segment
	TLNF			Teach me a Lesson i'll Never Forget
	TLO			Turn Indicator Lights Off
	TLW			Transfer and Lose Way
	TN			Take a Nap
	TOAC			Turn Off Air Conditioner
	TOG			Time Out, Graduate
	TOG			Take Out Garbage
	TOH			Take Operator Hostage
	TOO			Turn On/Off Operator
	TOP			Trap OPerator
	TOS			Trash Operating System
	TPD			Triple Pack Decimal
	TPDH			Tell Programmer to Do it Him/Herself
	TPF			Turn Power Off
	TPN			Turn Power On
	TPR			TeaR Paper
	TR			Turn into Rubbish [UNIX]
	TRA			Te Rdls Arvs [Type Ridiculous Abbreviations]
        TSH                     Trap Secretary and Halt
	TSM			Trap Secretary and Mount
	TST			Trash System Tracks
	TT%CN			TeleType - Clunk Noise
	TT%EKB			TeleType - Electrify KeyBoard
	TTA			Try, Try Again
	TTIHLIC  		Try To Imagine How Little I Care
	TTITT			Turn 2400 foot Tape Into Two 1200 foot Tapes
	TTL			Tap Trunk Line
	TTL			Time To Logoff
	TYF			Trust Your Feelings
			-U-
	UA			Unload Accumulator
	UAI			Use Alternate Instrucction set
	UAPA(AM)		Use all Power Available (And More)
	UCB			Uncouple CPU and Branch
	UCK			Unlock Console Keyswitch
	UCPUB			Uncouple CPU's and Branch
	UDR			Update and Delete Record
	UER			Update and Erase Record
	UFO			Unidentified Flag Operation
	ULDA			UnLoaD Accumulator
	UMR			Unlock Machine Room
        UNPD                    UNPlug and Dump
	UOP			Useless OPeration
	UP			Understand Program(mer)
	UPA			Use all Power Available
	UPC			Understand Program(mer)'s Comments
	UPCI			Update Card In Place
	UPI			Undo Previous Instruction (only in EMACS)
	URB			Update, Resume and Branch
	UTF			Unwind Tape onto Floor
	UTF			Use The Force
	UUBR			Use Undefined Base Register
			-V-
	VAX			Violate All eXecutions
	VFE			Violate Field Engineer
	VFO			Violate Female Operator
	VMA			Violate Maintenance Agreement
	VNO			Violate Noise Ordinance
	VPA			Vanishing Point Arithmetic
	VVM			Vaporize Virtual Memory
			-W-
	WAD			Walk Away in Disgust
	WAT			WAste Time
	WBB			Write to the Bit Bucket
	WBT			Water Binary Tree
	WC			Waste Core [UNIX]
	WCR			Write to Card Reader
	WDR			Warp disk DRive
	WED			Write and Erase Data
	WEMG			Write Eighteen Minute Gap
	WF			Wait Forever
	WGPB			Write Garbage in Process-control Block
	WHFO			Wait Until Hell Freezes Over
	WHP			Wave Hands over Program
	WI			Write Illegibly
	WI			Why Immediate
	WID			Write Invalid Data
	WNHR			Write New Hit Record
	WNR			Write Noise Record
	WPET			Write Past End of Tape
	WPM			Write Programmer's Mind
	WSE			Write Stack Everywhere
	WSWW			Work in Strange and Wonderous Ways
	WUPO			Wad Up Printer Output
	WWLR			Write Wrong-Length Record
	WWR			Write Wrong Record
	WSWW			Work in Strange and Wondrous Ways
			-X-
	XIO			eXecute Invalid Opcode
	XKF			eXecute Kermit the Frog
	XMB			eXclusive MayBe
	XOH			eXecute no-Op and Hang
	XOR			eXecute OpeRator
	XOS			eXchange Operator's Sex
	XPR			eXecute Programmer
	XPSW			eXecute Program Status Word
	XSP			eXecute Systems Programmer
	XVF			eXchange Virtue for Fun
			-Y-
	YAB			Yet Another Bug
	YASE			Yet Another Stupid Error
			-Z-
	ZAP			Zero and Add Packed
	ZAR			Zero Any Register
	ZD			Zap Directory
	ZEOW			Zero Every Other Word
	ZPI			ZaP Immediate



Sperry (Unisys) 1100/90 Opcodes :

AGB   Add GarBage
BBL   Branch on Burned out Light
BAH   Branch And Hang
BLI   Branch and Loop Infinite
BPB   Branch on Program Bug 
BPO   Branch if Power Off
CPB   Create Program Bug
CRN   Convert to Roman Numerals
DAO   Divide And Overflow
ERS   Erase Read-only Storage
HCF   Halt and Catch Fire
IAD   Illigical And
IOR   Illogical Or
MDB   Move and Drop Bits
MWK   Multiply WorK
PAS   Print And Smear
RBT   Read and Break Tape
RPM   Read Programmer's Mind
RRT   Record and Rip Tape
RSD   Read and Scramble Data
RWD   ReWind Disk
TPR   Tear PapeR
WED   Write and Erase Data
WID   Write Invalid Data
XIO   Execute Invalid Opcode
XOR   Execute OperatoR
XPR   Execute ProgrammeR
-- 
                        /\                    ?               ________________ 
jjo...@topaz.rutgers.edu \  ____   __       fgu             |.signature under|
 Anything is possible...   \ |  |  / |     orywlut-          |  construction  |
                            ==========    gfgsdfsdfsd        |________________|
_____________________________OO_____O___hfdhksjdhfksjdfs_______||__________||__


-Alan
Stay away from hurricanes for a while.

pet...@opus.cs.mcgill.ca (Peter Deutsch) writes:

>In article <1713@cygnus.scol.UUCP>, davidgu@scol.UUCP (David Gurr) writes:
>> dc...@cssun.tamu.edu (David A. Cook) writes:
>> 
>> >In article <ben.2630@epmooch.UUCP> ben@epmooch.UUCP (Rev. Ben A. Mesander) 
>> >writes:
>> >> If memory serves me right, the old Commodore PET machines could be
>> >> physically damaged (ie smoke) by poking the wrong value into the wrong
>> >> memory location. Good design...
>> 
>> Didn't there use to be a machine intrsuction that caused this problem?
>> Some wag gave it the mnemonic HCF ... Halt and Catch Fire!

No. The PET used the Mos Technology 6502 processor. HCF is a 6800
instruction.

The Motorola 6800 processor had an undocumented instruction
(code 0x9d), which transformed the cpu into a fast binary counter
on the address bus. It was otherwise dead, not even a NMI could
awake it. I got this information (and the mnemonic HCF, Halt and
Catch Fire for the instruction) from an article in Byte:

   G. Wheeler, "Undocumented M6800 instructions", Byte, 
   December 1977, page 46-48

The purpose of this instruction was perhaps some kind of 
factory test. I don't think it could do any hardware damage.

Wolfgang Strobl
#include <std.disclaimer.hpp>

In article <3061.2...@cc.helsinki.fi> mnyk...@cc.helsinki.fi writes:
>In article <ben.2630@epmooch.UUCP>, ben@epmooch.UUCP (Rev. Ben A. Mesander) writes:
>> If memory serves me right, the old Commodore PET machines could be
>> physically damaged (ie smoke) by poking the wrong value into the wrong
>> memory location. Good design...
>The original PC could control the voltage going to the monitor, I've
>heard, with similar results..

	The Soviet BESM-6 could adjust the secondary power supply
	voltage with software means! So one could alert surge protectors
	(and turn off the machine) by moving voltage up-down-up-down
	several times. /BESM-6 was in mass-production about 18 years!
	An unique occasion, isn't it?/

	Vadim Antonov
	DEMOS, Moscow, USSR
	(It is NOT a joke!)

	The joke about rewinding fans resembles me one real case:
	I was mastering Unix-like system for East German ugly
	brain-damaged PDP-11 clone (K1630) and have found the
	non-DEC trap "FAN FAILURE" !
	I did not invent any reasonable reaction on that trap. ;-)

	/This BD machine was designed at Robotron (East Germany).
	(We used nickname "Grobotron" for Robtron's machines :-),
	I've heard that one silly Western company bought Robotron
	few weeks ago. Good luck, guys!/  :-)

	Could anybody say me why (practically?) all German machines are
	equipped with power switch on a rear panel, so one have to
	seek for it for some minutes? ;-)

	Vadim Antonov
	DEMOS, Moscow, USSR
	(It is NOT a joke!)

In article <3061.2...@cc.helsinki.fi> mnyk...@cc.helsinki.fi writes:
>The original PC could control the voltage going to the monitor, I've
>heard, with similar results..

   Actually, what could (can) be done was to reprogram the video
controller chip to give an unexpected scan rate. This being before
Multisync monitors =8) the flyback transformer would start generating
lots of extra heat, and could eventually catch fire. (At least I think
it was the flyback. The flyback is the generic folklore monitor component,
anyway, after maybe the crt itself...) I think that at one time there was
even a virus written to do this. However, because you had to *wait* for the
heat to build up in the xformer, it took (I hear) about half an hour, with
the picture meanwhile completely unreadable, to do any permament damage, 
so this couldn't exactly be done subtly ...


-- 
wi...@milton.acs.washington.edu       Seattle, Washington  | No sig under
(William Lewis)   |  47 41' 15" N   122 42' 58" W  |||||||| construction

In article <3061.2...@cc.helsinki.fi>, mnyk...@cc.helsinki.fi writes:
> In article <ben.2630@epmooch.UUCP>, ben@epmooch.UUCP (Rev. Ben A. Mesander) writes:
> > If memory serves me right, the old Commodore PET machines could be
> > physically damaged (ie smoke) by poking the wrong value into the wrong
> > memory location. Good design...
> The original PC could control the voltage going to the monitor, I've
> heard, with similar results..
> -- 
> Matti Nyk{nen			CS Student at Helsinki U, Finland

Close, Matti, but no cigar.  (But the smoke was indeed there.)

The PC display adapters (all of them) can AND MUST generate a sync signal
at the sweep rate that the monitor expects.  This rate is software-adjustable.
When you call the BIOS function that sets the video mode, that's one of the
things the BIOS code does.  But if you're brave and knowledgeable, you
can do it from your own ASM program.

Well, the original IBM monochrome monitor (not the PC itself) had a
sweep circuit that was NOT free-running; if it didn't get sweep sync
signals from the PC often enough, it just sat there pumping current
into the deflection circuits.  Leave a large current like that on
long enough and the deflection circuit generates blue smoke  :-(

OK, so if your ASM program that sets the sweep rate screws up and
sets the rate way too low........

Dave

In article <3061.2...@cc.helsinki.fi> mnyk...@cc.helsinki.fi writes:

   > If memory serves me right, the old Commodore PET machines could be
   > physically damaged (ie smoke) by poking the wrong value into the wrong
   > memory location. Good design...
   The original PC could control the voltage going to the monitor, I've
   heard, with similar results..

Some of the HP-9000/200 Series machines would supposedly smoke the monitor
if you set a display register incorrectly... ( What if... )

-randy

-- 
Randy Welch   Mail to :  ...!ncar!scicom!bldr!randy or rwe...@du.edu
Boulder, CO   VOICE   :  303-442-6717
"Unfortunately, life contains an unavoidable element of unpredictability"
-David Lynch "The Angriest Dog in the World"

mnyk...@cc.helsinki.fi writes:

>In article <ben.2630@epmooch.UUCP>, ben@epmooch.UUCP (Rev. Ben A. Mesander) writes:
>> If memory serves me right, the old Commodore PET machines could be
>> physically damaged (ie smoke) by poking the wrong value into the wrong
>> memory location. Good design...
>The original PC could control the voltage going to the monitor, I've
>heard, with similar results..

I've heard (well, read on USENET ;-) that the Atari ST can be physically
damaged if the right port on the MMU is set to toggle *very* frequently.
The thing seems to be that the chip can't dissipate the heat generated
by the continuous toggling, and then overheats, ho humm.

	Jens
Jens Tingleff MSc EE, Institute of Computer Science, Copenhagen University
Snail mail: DIKU Universitetsparken 1, DK2100 KBH O
"It never runs around here; it just comes crashing down"
	apologies to  Dire Straits 

In article <1990Sep10....@hq.demos.su>, a...@hq.demos.su (Vadim G. Antonov) writes:
> 	The joke about rewinding fans resembles me one real case:
> 	I was mastering Unix-like system for East German ugly
> 	brain-damaged PDP-11 clone (K1630) and have found the
> 	non-DEC trap "FAN FAILURE" !
>
I once heard an interesting story about a Soviet PDP-11 clone. I was talking
to a guy that seems to be kind of a meta field-service engineer with DEC;
in other words, if he can't fix it it doesn't get fixed. He said that the
US State department called one day and dropped off a Soviet clone of the
11/34. They had obtained it from DEC in Italy; a company there had bought
it from some other company and called DEC asking for field service. DEC
showed up and discovered it wasn't theirs, so they thought the State
Department might be interested. I guess not...

> 	Could anybody say me why (practically?) all German machines are
> 	equipped with power switch on a rear panel, so one have to
> 	seek for it for some minutes? ;-)

No, but I did hear a good explanation for why IBM mainframes are so
user-hostile once. It seems that IBM once lost a court case and was ordered
by the court to build its machines such that they could not be used for
criminal activities. The joke is that they succeeded; since the machines
can't be used at all, they can't be used for criminal activities. Any
nice usable user interface would be a violation of court order, so they
can't improve it.

===============================================================================
Roger Ivie

35 S 300 W
Logan, Ut.  84321
(801) 752-8633
===============================================================================

In article <3061.2...@cc.helsinki.fi>, mnyk...@cc.helsinki.fi writes:
> In article <ben.2630@epmooch.UUCP>, ben@epmooch.UUCP (Rev. Ben A. Mesander) writes:
> > If memory serves me right, the old Commodore PET machines could be
> > physically damaged (ie smoke) by poking the wrong value into the wrong
> > memory location. Good design...
> The original PC could control the voltage going to the monitor, I've
> heard, with similar results..


Survey says! Bzzzzzzzz.

Sorry, not quite. What you could do was program the
horizontal and vertical trace frequencies from software.
Thus, you could set the horizontal frequency to zero. This
produced a high current through the flyback transformer,
which would toast it. Once you let the smoke out, it
wouldn't work any more (The PC screen, like everything
electronic, runs on smoke).

This is not quite the same as writing a program to "feed
200 volts to the screen", but produced a similar effect.

Note, exact niggly details ommitted. You want 'em get a
copy of the IBM PC Technical Reference manual or any of
the many "Underneath the Hood of the IBM PC for Power
Cobol Systems Programmers (Version II, with Turbo-Cobol
support!)"


			- peterd


--------------------------------------------------------------------------
+-------+ 	Peter Deutsch		McGill University
| u # u |	pet...@cs.mcgill.ca	School of Computer Science
|/\/\/\/|	
|  a a  |	
 \  a  /	"Love my work, hate my job..."
  \___/         
--------------------------------------------------------------------------

In article <73...@milton.u.washington.edu>, wi...@milton.u.washington.edu (William Lewis) writes:
> In article <3061.2...@cc.helsinki.fi> mnyk...@cc.helsinki.fi writes:
> >The original PC could control the voltage going to the monitor, I've
> >heard, with similar results..
> 
>    Actually, what could (can) be done was to reprogram the video
> controller chip to give an unexpected scan rate. .  .  .

> Multisync monitors =8) the flyback transformer would start generating
> lots of extra heat, and could eventually catch fire. (At least I think
> it was the flyback. The flyback is the generic folklore monitor component,
> anyway, after maybe the crt itself...) I think that at one time there was
> even a virus written to do this. However, because you had to *wait* for the
> heat to build up in the xformer, it took (I hear) about half an hour, with
> the picture meanwhile completely unreadable, to do any permament damage, 
> so this couldn't exactly be done subtly ...

Of course, if a machine was left on overnight, a virus
checked the clock and set the scan rate to bozo-mode after
9pm, damage _could_ result. No, I know of no examples of
this, nor do I know of anyone who ever lost their PC
screen because of faulty scan rates, but heck, this is
folklore! :-)


			- peterd

And BTW, gosh I hope a...@hq.demos.su (Vadim G. Antonov) is
a real machine!?!? Maybe _that's_ why Bush and Gorbechev
had to meet last week?

In article <73...@milton.u.washington.edu> wi...@milton.u.washington.edu (William Lewis) writes:
>In article <3061.2...@cc.helsinki.fi> mnyk...@cc.helsinki.fi writes:
>>The original PC could control the voltage going to the monitor, I've
>>heard, with similar results..
>
>   Actually, what could (can) be done was to reprogram the video
>controller chip to give an unexpected scan rate. This being before
>Multisync monitors =8) the flyback transformer would start generating
>lots of extra heat, and could eventually catch fire. (At least I think
>it was the flyback. The flyback is the generic folklore monitor component,
>anyway, after maybe the crt itself...) I think that at one time there was
>even a virus written to do this. However, because you had to *wait* for the
>heat to build up in the xformer, it took (I hear) about half an hour, with
>the picture meanwhile completely unreadable, to do any permament damage, 
>so this couldn't exactly be done subtly ...
>
>wi...@milton.acs.washington.edu       Seattle, Washington  | No sig under
>(William Lewis)   |  47 41' 15" N   122 42' 58" W  |||||||| construction

	Specifically, it was the 6845 chip found on Hercules Graphics
Cards, and (I must assume) the original MDA.  This was not, and never
will be, a problem with color cards such as the CGA and on up.  Sync
timing values can be altered by the user, causing potentially (see note
below) damaging frequencies.

	I quote from the Hercules Technical Reference Manual:  "Speed in
programming the 6845 is vital.  While the 6845 is being programmed,
undefined control frequencies are being sent to the monitor.  If this
condition is unduly prolonged, monitor damange may result."

	Back when I was in high school, I heard this cautionary tale.
However, I to this day have never heard a first-hand account of this
happening.  Have you had this happen to you?  If you have, why not
post about it?  I should note that I actually *work* for Hercules Technology
and I know the guy who designed the original HGS personally.  Perhaps
I should ask him, he might have done it himself... :-)

	Anyway, I suspect that modern monitors (especially multisyncs,
of course) are built with enough tolerance that the user could shut
down their monitor upon seeing a loss of sync LONG before any damage
could be done.

Dylan Rhodes
No .sig file, I think...

In article <3061.2...@cc.helsinki.fi> mnyk...@cc.helsinki.fi writes:
>The original PC could control the voltage going to the monitor, I've
>heard, with similar results..
Actually, I seem to remember that the analog timing of the monochrome
and color displays was different and that forcing the wrong one caused
the flyback transformer to smoke out.

Then again, I don't know analog electronics, so take it with a lot of salt.


-- 
==============================================================================
#include <disclaim.std>
==============================================================================

In alt.folklore.computers, a...@hq.demos.su (Vadim G. Antonov) writes:
>/This BD machine was designed at Robotron (East Germany).
>(We used nickname "Grobotron" for Robotron's machines :-),
>I've heard that one silly Western company bought Robotron
>few weeks ago. Good luck, guys!/  :-)

This has to be "Robotron" as in Robotron Soemmerda, a soccer team in the
East German 2nd Division. I heard from an East German that they made toys at
Soemmerda - it's a small town in the south.

The team (and probably the company) have now been renamed "Soemtron",
presumably to avoid massive lawsuits with Williams Corp. (:

In article <12...@asylum.SF.CA.US> shark@asylum.UUCP (Dylan Rhodes) writes:
>	Anyway, I suspect that modern monitors (especially multisyncs,
>of course) are built with enough tolerance that the user could shut
>down their monitor upon seeing a loss of sync LONG before any damage
>could be done.

True.  It also makes a pretty horrible screeching noise.

We used to do video animation with a Silicon Graphics 4D/70GT.  The system
could be switched from standard raster mode (60 Hz, non-interlace) to NTSC
mode (30 Hz, interlace) for input to a transcoder.  The sound the monitor made
was horrible.  We never forgot to shut it off :-).  I suspect that the
electronics in the monitor were none too happy about being driven at NTSC
rates.

							spl (the p stands for
							PLEASE stop that
							noise...)
-- 
Steve Lamont, SciViGuy -- (408) 646-2752 (subject to change at random)
NPS Confuser Center / Code 51 / Naval Postgraduate School / Monterey, CA 93940
"You're okay," said Honeysuckle.  "The dogs like you."
			- Charles Bukowski, "How to Get Published"

In article <22...@opus.cs.mcgill.ca>, pet...@opus.cs.mcgill.ca (Peter Deutsch) writes:
> In article <3061.2...@cc.helsinki.fi>, mnyk...@cc.helsinki.fi writes:
> > In article <ben.2630@epmooch.UUCP>, ben@epmooch.UUCP (Rev. Ben A. Mesander) writes:
> > > If memory serves me right, the old Commodore PET machines could be
> > > physically damaged (ie smoke) by poking the wrong value into the wrong
> > > memory location. Good design...
> > The original PC could control the voltage going to the monitor, I've
> > heard, with similar results..
> 
> 
> Survey says! Bzzzzzzzz.
> 
> Sorry, not quite. What you could do was program the
> horizontal and vertical trace frequencies from software.
> Thus, you could set the horizontal frequency to zero. This
> produced a high current through the flyback transformer,
> which would toast it. Once you let the smoke out, it
> wouldn't work any more (The PC screen, like everything
> electronic, runs on smoke).
> 

Actually, back in the days when the big, bad software companies thought
they could get away with copy protection, there was a system developed that
would do this to your monitor if it determined you were using an
illegal copy.  As I remember the PC-Week article, Ashton-Tate was looking
at using this on dBase III.  Talk about user-unfriendly software :-?


-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
David Wexelblat             | dw...@mtgzx.att.com    | They recommended
AT&T Bell Laboratories      | ...!att!mtgzx!dwex    |    euthanasia
200 Laurel Ave - 4B-421     |                       | For nonconformists
Middletown, NJ  07748       | (201) 957-5871        |    everywhere

In article <3307@gmdzi.UUCP> strobl@gmdzi.UUCP (Wolfgang Strobl) writes:
>The Motorola 6800 processor had an undocumented instruction
>(code 0x9d), which transformed the cpu into a fast binary counter
>on the address bus. It was otherwise dead, not even a NMI could
>awake it. I got this information (and the mnemonic HCF, Halt and
>Catch Fire for the instruction) from an article in Byte:
>
>   G. Wheeler, "Undocumented M6800 instructions", Byte, 
>   December 1977, page 46-48
>
>The purpose of this instruction was perhaps some kind of 
>factory test. I don't think it could do any hardware damage.

Right you are.  It was more popularly called WTD (Walk The Dog),
and is unbelievably handy when debugging the address bus, memory
systems, and so on.  It generated READ cycles at incrementing addresses,
wrapping from $FFFF to $0000, and repeating forever until *RESET
was asserted.  It made it really easy to find things like stuck address
bits, open bus signals, incorrect memory decoding, and the like.

It's been almost 15 years, but if memory serves :-) there were two
kinds of Walk The Dog instructions.  One, I think $9C, started at
address 0.  The other, I think $9D, took a 16-bit operand which was
the address to start walking from.

Jumping into data, or into the operand of an instruction, quite
often would eventually cause a WTD instruction to be executed, and
then we were off and walking.

>
>Wolfgang Strobl
>#include <std.disclaimer.hpp>

-Eric

-- 
Eric Black	"Garbage in, Gospel out"
Atherton Technology, 1333 Bordeaux Dr., Sunnyvale, CA, 94089
  Email: er...@Atherton.COM     Voice: +1 408 734 9822

>In article <1990Sep10....@hq.demos.su>, a...@hq.demos.su (Vadim G. Antonov) writes:
>> 	The joke about rewinding fans resembles me one real case:
>> 	I was mastering Unix-like system for East German ugly
>> 	brain-damaged PDP-11 clone (K1630) and have found the
>> 	non-DEC trap "FAN FAILURE" !

Back in 1982 or 83, the Bally/Midway company came out with the arcade game
"Tron", after the movie.  It had the best graphics in the arcade when it first
came out, and was one of the more complex games.

Folklore says that the US Government wouldn't allow Bally to ship the game to
Eastern Europe, because the processor used in "Tron" was more complex than
anything the Soviets had at the time.

	Darrin

mdchaney@iubacs
mdch...@bronze.ucs.indiana.edu
mdch...@rose.ucs.indiana.edu

The year was 1984.  The machine was one of the original Compaq portables
(now frequently called "luggable" -- expect one arm to get substantially
longer than the other if you ever have to carry one across O'Hare airport).

The Compaq featured one of the original multi-sync monitors.  It synched
at 50 Hz like the IBM Mono Monitor, and at 60 Hz like the IBM Color
Monitor.

I had just finished writing a customized video driver (to replace INT 10h).
I added a line to the CONFIG.SYS file and re-booted.

About 5 seconds into the boot process, the monitor went blank, and the
high-pitched whine of the horizontal flyback stopped.  I had just begun
to scratch my head when I got the first whiff of the telltale smell of
burning resisters.

I immediately powered off the machine.  I have no doubt that permanent
damage would have been done if I had left it in the erroneous state.

Desk-checking revealed a bug in the code that loaded up the registers
in the 6845 video controller -- byte swap issues between the little
endian 8088 and the big endian 6845.

-- Jim Lyon
   ji...@tandem.com

sh...@asylum.SF.CA.US (Dylan Rhodes) writes:
>	Back when I was in high school, I heard this cautionary tale.
>However, I to this day have never heard a first-hand account of this
>happening.  Have you had this happen to you?  If you have, why not
>post about it?  I should note that I actually *work* for Hercules Technology
>and I know the guy who designed the original HGS personally.  Perhaps
>I should ask him, he might have done it himself... :-)

My original IBM PC had both a monochrome monitor and a CGA monitor hooked up
(ooh, aah, high-tech), and when we needed some work on it (something really
simple, like upgrading the BIOS, but this was back when I knew next to nothing
about the system), we took it to our local Computerland.  When they returned
the system, they had set the DIP Switches to boot on the color monitor, which
was warned against in the Guide to Operations in big bold letters, but I didn't
know that, and of course Computerland didn't.

The system booted normally, but the monochrome card never got its signals
straight, and after about three minutes, there was a single flash from the
monochrome monitor, after which it was completely dead.  We sent it to
Computerland (our second mistake), and eventually got them to pay for the
repairs.

But it *can* happen.

>Dylan Rhodes

-- 
Kevin Martin  |||  si...@pawl.rpi.edu  |||  usergkj1@RPITSMTS.BITNET

If my memory serves me right, the Hercules graphics card programming
instructions used to warn programmers that incorrect programming of
the card could cause damage to the monitor and/or the card. The Herc, of
course, uses the 6845 ...

I'd never heard of anyone actually screwing it up that well tho' ! :-)

----------------------------------------------------------------------
Dave Gurr			..!uunet!mcsun!ukc!slxsys!scol!davidgu
Santa Cruz Operation Ltd.

Disclaimer: All opinions expressed are those of the author's cat, not
necessarily those of the author, and almost certainly NOT those
of SCO Ltd.  Miaouw.
----------------------------------------------------------------------

In article <22...@opus.cs.mcgill.ca>, pet...@opus.cs.mcgill.ca (Peter Deutsch) writes...
>In article <73...@milton.u.washington.edu>, wi...@milton.u.washington.edu (William Lewis) writes:
>> In article <3061.2...@cc.helsinki.fi> mnyk...@cc.helsinki.fi writes:
>> >The original PC could control the voltage going to the monitor, I've
>> >heard, with similar results..
>> 
>>    Actually, what could (can) be done was to reprogram the video
>> controller chip to give an unexpected scan rate. .  .  .
> 
>> Multisync monitors =8) the flyback transformer would start generating
>> lots of extra heat, and could eventually catch fire. (At least I think
>> it was the flyback. The flyback is the generic folklore monitor component,
>> anyway, after maybe the crt itself...) I think that at one time there was
>> even a virus written to do this. However, because you had to *wait* for the
>> heat to build up in the xformer, it took (I hear) about half an hour, with
>> the picture meanwhile completely unreadable, to do any permament damage, 
>> so this couldn't exactly be done subtly ...
> 
>Of course, if a machine was left on overnight, a virus
>checked the clock and set the scan rate to bozo-mode after
>9pm, damage _could_ result. No, I know of no examples of
>this, nor do I know of anyone who ever lost their PC
>screen because of faulty scan rates, but heck, this is
>folklore! :-)
> 
> 
>			- peterd

I had a friend who worked for a computer store in Wasilla, Alaska... He did
some programming work for them (ie demos, etc.). The store ended up owing him
~$1000... and they wouldn't pay. So, he wrote a program that burned out monitors
by focusing the scan rate of the monitor on one spot....
Ran it on a few of the more expensive monitors... and got the $1000 dollars out
of them!!

Marc A. Casillo                         AXMAC@ALASKA.BITNET
Student User Consultant                 AX...@ACAD3.FAI.ALASKA.EDU
University Of Alaska, Anchorage         CAS...@HAYES.FAI.ALASKA.EDU

In article <1990Sep12....@tandem.com> ji...@tandem.com (Jim Lyon) writes:

#The year was 1984.  The machine was one of the original Compaq portables
#(now frequently called "luggable" -- expect one arm to get substantially
#longer than the other if you ever have to carry one across O'Hare airport).

It is a marvelous feature still used in portable computers today. When you 
pack 'em up in your apartment, they're feather-light, but by the time you
get them into your car, drive them to JFK airport, park, walk to your plane,
fly them across country for five hours, drag them across San Francisco 
Airport, get them to the rental car, and take them up to your hotel room --
by the time you've done all that, they weigh as much as a refrigerator
which could feed a family of eight!

Where does the extra mass come from?

-- 
                                                        -- Mitch Wagner

VOICE: 516/562-5758                                   GEnie: UNIX-TODAY
UUCP: wag...@utoday.com                          ...uunet!utoday!wagner

In article <1730@cygnus.scol.UUCP> davidgu@scol.UUCP (David Gurr) writes:
>
>If my memory serves me right, the Hercules graphics card programming
>instructions used to warn programmers that incorrect programming of
>the card could cause damage to the monitor and/or the card. The Herc, of
>course, uses the 6845 ...
>
>I'd never heard of anyone actually screwing it up that well tho' ! :-)
>
>Dave Gurr			..!uunet!mcsun!ukc!slxsys!scol!davidgu
>Santa Cruz Operation Ltd.
>

	Yes, you're exactly correct.  In fact, I quoted some Hercules
documentation to that effect the other day.

	I work for Hercules, but I didn't get there until last year.
Spoke to the guy who was the original Tech Support Manager (and sole
Tech Support employee) last week after reading the melting monitor
thread.  Here's some actual verified information (as opposed to wild
rumors):

	It seems that in the early days, IBM distributed a program
called something like "Welcome to the IBM PC" or "About your PC"
(or something like that - so much for verified information) that wasn't
too keen on third-party video cards (of which there was only one - the
Hercules mono card).  So users would get their IBMs, replace their MDAs
with Hercules Cards (instead of spending $1000 on a CGA card/monitor combo)
keep their cheap IBM mono monitors, and then run IBM's demo program.
And, in true IBM fashion, the program would go into graphics mode by setting
up some CGA-specific sync values.  In almost no time at all the user had
a dead monitor, and Hercules (very benevolently, I think) purchased the user
a new monitor!

	That wasn't a big problem for Hercules at the time, though.  They
were making more money than they knew what to do with.  Most of the company
cars - like the Porsche 928, which I hope *I* get to drive someday - are
from the '83 - '85 era.

Dylan Rhodes
No .sig...

	

Apparently in one of the early Tandy main frames, the engineers included
an error message for when the machine was physically bumped. Since this
condition is so rare while the machine is running, it went un-noticed
until the machine was out on the market. The first irate and confused
costumer received dis-belief from technical support when they reported
the message:

"Beam me up Scotty, I'm sucking mud!"

John Huebner 
jh...@andrew.cmu.edu

   I remember years ago being able to do something like you described
(having resistors burning, etc on your Compaq) on my high school's
Commodore Pet machines.
 
   I used to have a list of what I called "Killer pokes" that you
could input to do very strange things to the monitor.. The 
high-pitched buzzing wasn't enough for me.. I was able to get the
whole screen to compress to 1 pixel on the actual screen!
 
   It was the whitest dot I've ever seen on a green monitor.  I 
wasn't cruel enough to leave it on to do some real damage, but
it was exciting at the time.
 
-- 
)> Frank Lemire <(  frankl@{xrtll,torag,pnet91,intacc}.UUCP (pick one!)
)> Toronto, CA. <(  INET: geac!torag!fra...@gpu.utcs.toronto.edu
                                 "You're only a rebel from the waist downwards."
                                                        - Winston Smith in 1984.

In article <12...@asylum.SF.CA.US>, sh...@asylum.SF.CA.US (Dylan Rhodes) writes:
|> 
|> 	Back when I was in high school, I heard this cautionary tale.
|> However, I to this day have never heard a first-hand account of this
|> happening.  Have you had this happen to you?  If you have, why not
|> post about it?  I should note that I actually *work* for Hercules Technology
|> and I know the guy who designed the original HGS personally.  Perhaps
|> I should ask him, he might have done it himself... :-)
|> 

	Well, I have an AT clone with a herc (or herc clone, not sure, but it works like one) card in it, which certainly _did_ lead to the destruction of my mono monitor.

	I wanted a screen saver. Along I went to my Uni's PC-SIG CD rom, and snaffled a likely looking one. I ran it on my system at home, seemed to work fine the first time I ran it and let the screen blank out (though not for long), so I walked away to the other end of the house. 

	I came back half an hour later. Screen "saved" itself alright, it was blank, but there was a pitiful high pitched noise coming out of it. That's all she wrote, that screen never did anything except make said pitiful noise from that point on. It was a write-off.

	I use to think this sort of story was bullshit too. It ain't, it happens.

	Simon Hackett
	si...@itd.adelaide.edu.au, Adelaide South Australia
	(a.k.a. hac...@asylum.sf.ca.us)

In article <1803@utoday.UUCP> wagner@utoday.UUCP (Mitch Wagner) writes:
>In article <1990Sep12....@tandem.com> ji...@tandem.com (Jim Lyon) writes:
>#The year was 1984.  The machine was one of the original Compaq portables
>#(now frequently called "luggable" -- expect one arm to get substantially
>#longer than the other if you ever have to carry one across O'Hare airport).
>
>It is a marvelous feature still used in portable computers today. When you 

  I had many good years of service out of my trusty SX-64 Bodybuilder model
personal computer.  My spine was probably only compressed about an inch, at
least permanently - the rest has sprung back over the years.  (why ANYONE
would put a 27 pound heat sink on the back of a machine which already has
a metal case...)

>by the time you've done all that, they weigh as much as a refrigerator
>which could feed a family of eight!
>
>Where does the extra mass come from?

Ah, well, this is a complex and subtle question.  It has to do with the
interrelation between time and matter, called Specific Relativity.  You 
see, while you are transporting a computer in a gravitational field, the
molecular bonds of most metals and semiconductors gain weight due to 
plasmic pseudo-hyperbonding.  Thus, the actual time spent in motion 
relative to an observer relaxing at rest becomes one of the variables in
the weight function.  So, in fact, no additional "mass" as such is 
involved, but local space tends to warp itself roughly around your power 
supply transformer.  The obvious result of this is that, to you, your
arm seems to be getting weaker over time - but it's all merely an 
unfortunate result of the physics of computing.

And no, I will not post a disclaimer - the ONLY reason I flunked physics
twice is that my instructor had an unhealty obsession with exam results.
 
.                            <<<<Infinite K>>>>

--
.---------------------------------------------------------------------------.
|Ben Scott, professional goof-off and consultant at The Raster Image, Denver|
|Amiga UUCP node domain: bsc...@vila.denver.co.us Else: bsc...@nyx.cs.du.edu|
|FIDO point address 1:104/421.2, or call the Arvada 68K BBS at (303)424-9831|
|"Don't embarrass us..."  "Have I ever?" - Buckaroo Banzai  | *AMIGA POWER* |
`---------------------------------------------------------------------------'

We had a Hungarian-made Videoton-340 ASCII terminals
in the Moscow State University. They were hooked to BESM-6s. Just
plain old ASCII terminals (80x16 no lowercase) except one of them:
with one side of the monitor lifted the cursor slided down to the
opposite side. No reasonable explanation was ever invented.
-- 
Dmitry V. Volodin <d...@hq.demos.su>     |
fax:    +7 095 233 5016                 | We are smart guys, ain't we?
phone:  +7 095 231 2129                 |

In my highschool we had Apple II's and frustrated students would repeatedly
hit and hold the reset key numerous times.  It eventually produces a dump
of ROM or something.  Shortly afterwards smoke starts coming out of the machine.
I don't believe we ever lost a machine though.