test-drb February 2003

test-drb@ccmp.vtda.org

337 participants
780 discussions

by ekklein＠pacbell.net

I recently acquired a California Computer Systems model 2422 Floppy Disk Controller Rev B. (S-100) in what appears to be good condition but missing a 2716 EPROM presumably containing the onboard BIOS. Does anyone have this card and the capability of providing me with a copy of the PROM or at least a dump of it? I'd also love to get my hands on the docs, if available. Thank you, Erik

21 years, 10 months

Interesting finds

by Fred.van.Kempen＠microwalt.nl

Hi, While hauling some VAX and StorageWorks stuff yesterday, I bumped into a Philips PTS6000 machine (actually, two.. a larger one, and a smaller one), some HP stuff (looks like HP Big Iron) and the cabinet of a DECarray system. Anyone interested? Pics available. --fred

21 years, 10 months

PS2 Mouse

by teoz＠neo.rr.com

I was wondering if there ever was a PC PS2 type mouse addon card for old 386 or previous AT type computers? I know there were bus mice, but thats not the same. The reason I am asking is because I have a PS2 KVM switch and want to get my 386/DX40 computer connected to it (it doesnt have a ps2 header).

21 years, 10 months

6502 cycles and subtleties (was Re: Assembly on a Apple IIc+)

by pete＠dunnington.u-net.com

On Feb 9, 10:55, Eric Smith wrote: > > Are you sure? My understanding is that PLP and PLA increment the stack > > pointer *before* fetching the byte off the stack. > [...] > > Maybe you're thinking of PHP and PHA ([SP]:=A; SP:=SP+1), which take one > > cycle less than PLP/PLA? > > You're right, I was confused. Phew! I was beginning to wonder if the 6502 is more bizarre than I already knew :-) You missed the mistake though -- I should have written SP:=SP-1 (no it wasn't a test, I only just noticed). -- Pete Peter Turnbull Network Manager University of York

21 years, 10 months

6502 cycles and subtleties (was Re: Assembly on a Apple IIc+)

by pete＠dunnington.u-net.com

On Feb 8, 19:02, Eric Smith wrote: > Well, I haven't counted them, but pretty much all instructions that > use the ALU do that. This includes ADC, SBC, ORA, AND, EOR, BIT, > and (when the accumulator is the destination) LSL, ASR, ROR, and ROL. > And the PLP and PLA instructions, which increment the stack pointer > using the ALU during the next fetch. Are you sure? My understanding is that PLP and PLA increment the stack pointer *before* fetching the byte off the stack. The 6502 stack pointer always points to the next free location on the stack. It's possible that it does something like: fetch instruction decode, and set up ALU to generate SP+1 fetch [SP+1] add 1 to SP while fetching next instruction Maybe you're thinking of PHP and PHA ([SP]:=A; SP:=SP+1), which take one cycle less than PLP/PLA? -- Pete Peter Turnbull Network Manager University of York

21 years, 10 months

PS2 Mouse

by teoz＠neo.rr.com

PS2 works off the keyboard controller, I was hoping somebody might have made a specialty board with keyboard controller allowing older machines to use ps2 hardware ----- Original Message ----- From: +ACI-John Allain+ACI- +ADw-allain+AEA-panix.com+AD4- To: +ADw-cctalk+AEA-classiccmp.org+AD4- Sent: Sunday, February 09, 2003 12:37 PM Subject: Re: PS2 Mouse +AD4- +AD4- I could use a USB +AD0APg- PS/2 mouse adapter, so far I have not +AD4- +AD4- found any such animal. I've found plenty that go the other way. +AD4- +AD4- Think this is one. It isn't a passthru. +AD4- http://www.cyberguys.com/cgi-bin/sgin0101.exe?T1+AD0-131+-0870 +AD4- +AD4- +AD4- On the subject... +AD4- I see a lot of PS/2-female to RS232/D9-male adaptors. +AD4- I assume that these are for signal sensing mice, +AD4- since these adaptors Are passthru, and I get the impression +AD4- from this list that PS/2 signals aren't RS232. +AD4- +AD4- John A.

21 years, 10 months

PDP11 RSX-11M operating system manual

by anheier＠owt.com

Hi, I have a large binder containing a DEC PDP11 RSX-11M System Generation and Management Guide, version 3.2, June 1979. Also included is a RSX-11M/M-Plus MCR Operation Manual and two bound mini references. All are in excellent shape. Best offer + shipping. Thanks Norm

21 years, 10 months

Odd ideas that I've had lately...

by cb＠mythtech.net

>I'd hate to >hose the PalmOS flash - dunno if there's a way to get it back without >building your own external re-Flasher (in the case of the IIIs and older >that *have* removable SIMMs). I think they may have an ability to recover built in. I know when I upgraded the OS on my wife's IIIx, I had a problem with the upgrade, and the flash didn't complete. The Palm wouldn't boot and I thought I was hosed. But a check in the directions offered a recover method. There is a sequence of button presses you can do that drops the Palm into "debugger" mode, and from there, the upgrade utility could restart the flash process and write the OS again. Of course, you would need a copy of the Flash ROM/OS and a utility to write it. I know you can dump your current ROM to file with the tools in the Palm Emulator available from Palm... but the only tool I know to write it back to the Palm is their OS upgrade tool, which means you would have to shell out for the upgrade (or find someone else that already did and use the software that they have). -chris <http://www.mythtech.net>

21 years, 10 months

attache' where are you?

by paulm064＠icqmail.com

I have been searching for info of an old laptop computer i have . Following details are all i have found: Attache' Forefront 286 model : LV-286D power supply : 17Volt ? 2.7Amp ? Battery : 12Volt 2200mAH NiCAD 3 pin connector - 9.8"x2.1"x1.1" Has detachable keyboard. Does any know if manufacturer was taken over by another? Need details of power supply and battery connector pollarity and or gifs of same . Don't know where else to look. Thanks Paul

21 years, 10 months

6502 cycles and subtleties (was Re: Assembly on a Apple IIc+)

by pete＠dunnington.u-net.com

On Feb 8, 11:41, Eric Smith wrote: > Pete wrote: > > You must be thinking of some different 6502 to the rest of us :-) As > > Sellam said, no 6502 opcode takes less than two clock cycles to > > execute, and most take more (up to 7): the only 2-cycle instructions are > > the ones with implied addressing, like RTS, CLI, TAX, ... > > Not RTS, that takes a bunch. Oops, wrong column! Yes, it takes 6. > There is a little bit of pipelining internally, but it's not really > obvious. The last ALU operation of an instruction is generally done > during the same clock cycle as the fetch of the next instruction. > For instance, when you do an "ADC #35" instruction (add with carry > immediate), it's a two-cycle instruction, but it really takes three > cycles to complete -- the third cycle is overlapped with the following > instruction's fetch. During the first cycle the opcode is fetched, > during the second cycle the immediate operand is fetched, and during the > third cycle, which is the first cycle of the next instruction, the actual > add occurs. True. Most instructions don't work like that, though. > > There aren't two CPU cycles per clock cycle. Perhaps you're thinking of > > the fact that the 6502 uses a two-phase clock, and does part of the CPU > > cycle during phi-1, and part during phi-2? > > Perhaps the original poster thought that, but it's just the old standard > two-phase NMOS logic. It takes two phases to do just about anything > internally, so it's not a matter of doing two things sequentially in > one clock cycle. (A small number of things occur in parallel in some > cycles, though.) Yes, *I* know that, but I don't think Jim did :-) -- Pete Peter Turnbull Network Manager University of York

21 years, 10 months

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test-drb February 2003