test-drb May 2008

test-drb@ccmp.vtda.org

199 participants
350 discussions

by ajp166＠bellatlantic.net

> >Subject: Re: Minimal CP-M SBC design > From: "Chuck Guzis" <cclist at sydex.com> > Date: Sun, 18 May 2008 10:31:45 -0700 > To: cctalk at classiccmp.org > >> Date: Sun, 18 May 2008 10:09:45 +0100 >> From: Gordon JC Pearce > >> Aha, I disagree. You can't get at the innards of the 6120 at all, >> because it's a chip. If you want to get at the innards of an emulator >> then you can, although how accurately the emulator models the logic of >> the -8 might be an issue (my emulator doesn't model it at all, but >> largely does its own thing). > >I was going to reply along the same lines, but I felt it might not >have convinced my audience. Back in the old days of 22Nice, we added >an emulator feature that allowed a user to write his own port-mapping >code and include it with each program, allowing each individual >program to have its own simulated peripherals, if desired. > >This was no accident or a "feature for feature's sake". A customer >was replacing a controller on a large piece of CNC machine tooling >(they made trailers for large trucks). Communication with the >machine was largely RS-232, so that was no problem with the PC, but >the controller application directly manipulated a UARTs registers. >We rolled an emulator overlay for the UART that functionally mapped >the program's accesses to the PC's 8250-type UART. It worked right >on the first try and the customer was happy for many years--and we >changed not a byte of code in the original program, nor our basic >product. > >That's the beauty of emulation--if the original box uses a bizarre >interface or unobtainium chip, you can emulate it. MUCH easier than >trying to do the same in hardware. Modern PCs tend to have >sufficient excess horsepower that you can emulate just about any 80's >era device without impacting performance. That is the exact reverse case I was refering to. For that case and many others like it I agree heartily. One of the "sims" I use is VMware under Linux So I can run them crufy MS OSs without havignto invest hardware on a daily basis. Doesn't hurt that I can also use it run a sim in a sim like MyZ80 inside W98se on the fast Linux machine. >But, as I've said, I felt that I wasn't going to sway the hard-bitten >hardware folks. As you pointed out, the line between hardware and >software is getting very blurry indeed. Cheap, fast, >microcontrollers now give a new spin to tasks that would have >normally been accomplished with a pile of discrete logic and can now >be done with little more than software. It works for me where it fits. If I want Z80 hardware no amount fo sim will make me happy but at the same time I may use a sim to build code for that Z80. As I've done it that way and in reverse and also to solve the problem of hardware that is unobtaimium. Where it works, I want to emulate a PDP1, or replace a PDP-11. Where it doesn't work so well is when I want to run VMS on a MicroVAX with performance in the NVAX realm. Maybe time to chance the topic??? This is clearly outside the discussion of how to make a minimalist CP/M system ( maybe even SBC). Allison

16 years, 7 months

TEK 4105 terminal, which keyboard was used (needed)

by g-wright＠att.net

I have one of these here with out a Keyboard. any one know which keyboards can be used on it with out seeing smoke. Has a DIN connector Of coarse I'm open to offers from any one that many have a keyboard also............. Thanks, Jerry

16 years, 7 months

DEC8235 and MM57109N ICs

by aek＠bitsavers.org

>until you find that they want $5 for a PDF of a >datasheet. I have three large databook collections (including most of what was at Haltek). I had offered them to CHM, but they've changed their mind about wanting them, and they want the storage space back, so I'm going to chop a subset and scan them at 600dpi over the next few months. The duplicates will probably go up on eBay in 20-book lots. The big problem will be their size and postprocessing them. I don't know if Jay is going to want something this big on bitsavers.

16 years, 7 months

Any interest in TRS-80 DT-1 terminals?

by derschjo＠msu.edu

I have a pair of TRS-80 DT-1 terminals that I've had for awhile and that I don't think I'm ever going to use. I believe they work but I have not done much with them aside from powering them up. They come with dust-covers! (fancy!) Free to whomever wants 'em. They're kinda large (about TRS-80 Model III-sized) so I'd prefer not to ship, but if that's what it takes... If there's no interest I'll probably drop them off at RE-PC in Tukwila, WA in a week or so, maybe they'll find a happy buyer for them there :). Thanks, Josh

16 years, 7 months

Tip: scanning large documents in sections and stitching together

by legalize＠xmission.com

See <http://hugin.sourceforge.net/> for a tool that will allow you to stitch together a larger image from partial scans. This sounds like just the right tool to use when scanning large circuit diagrams on a scanner that can't capture the whole document in one pass. -- "The Direct3D Graphics Pipeline" -- DirectX 9 draft available for download <http://www.xmission.com/~legalize/book/download/index.html> Legalize Adulthood! <http://blogs.xmission.com/legalize/>

16 years, 7 months

DOS/Floppy backup program benchmarks

by cclist＠sydex.com

> Date: Mon, 12 May 2008 11:04:15 -0500 > From: Jim Leonard > What I would love to test is Central Point Backup (PC Backup?) prior to > version 6, which is the only version I had available to test. Versions > prior to 6 are supposed to contain code that supports the Option Board I > have in my 5160 for additional speed -- however, I'm not sure how much > speedup I could expect, since some of the faster programs in the > shootout must have been operating at a 1:1 intereave (I was writing all > 40 tracks both sides in less than 30 seconds per disk; can it get any > faster than that?). I'll dig out the old FastBack and see if I've got an older CP backup-- I may well have. If you're formatting then writing, then an OB might be faster, but probably not when simply writing to a formatted diskette, assuming that the sector layout is skewed appropriately to allow for seek and head settling times. In the bad old days of WD 17xx diskette controllers, we had a copy program that formatted and wrote backup data in one pass, as long as the data didn't have any of the "special" bytes that the WD chip interprets differently during a format operation. Cheers, Chuck

16 years, 7 months

Minimal CP-M SBC design

by cclist＠sydex.com

> Date: Sun, 18 May 2008 10:09:45 +0100 > From: Gordon JC Pearce > Aha, I disagree. You can't get at the innards of the 6120 at all, > because it's a chip. If you want to get at the innards of an emulator > then you can, although how accurately the emulator models the logic of > the -8 might be an issue (my emulator doesn't model it at all, but > largely does its own thing). I was going to reply along the same lines, but I felt it might not have convinced my audience. Back in the old days of 22Nice, we added an emulator feature that allowed a user to write his own port-mapping code and include it with each program, allowing each individual program to have its own simulated peripherals, if desired. This was no accident or a "feature for feature's sake". A customer was replacing a controller on a large piece of CNC machine tooling (they made trailers for large trucks). Communication with the machine was largely RS-232, so that was no problem with the PC, but the controller application directly manipulated a UARTs registers. We rolled an emulator overlay for the UART that functionally mapped the program's accesses to the PC's 8250-type UART. It worked right on the first try and the customer was happy for many years--and we changed not a byte of code in the original program, nor our basic product. That's the beauty of emulation--if the original box uses a bizarre interface or unobtainium chip, you can emulate it. MUCH easier than trying to do the same in hardware. Modern PCs tend to have sufficient excess horsepower that you can emulate just about any 80's era device without impacting performance. But, as I've said, I felt that I wasn't going to sway the hard-bitten hardware folks. As you pointed out, the line between hardware and software is getting very blurry indeed. Cheap, fast, microcontrollers now give a new spin to tasks that would have normally been accomplished with a pile of discrete logic and can now be done with little more than software. Cheers, Chuck

16 years, 7 months

Free (or price of shipping) Stuff -- Part 1

by btt＠hughes.net

I would be inetersted in all the apple iic stuff, and the apple joystick a2m2012. I live in Ohio, 45107. Do you still have these items? Brian Ties

16 years, 7 months

Minimal CP-M SBC design

by ajp166＠bellatlantic.net

> >Subject: Re: Minimal CP-M SBC design > From: Gordon JC Pearce <gordonjcp at gjcp.net> > Date: Sun, 18 May 2008 10:09:45 +0100 > To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org> > >On Sun, 2008-05-11 at 16:25 -0400, Allison wrote: > >> Bob's SBC6120 is as close or better than a real 8e for playing with code. >> >> That s the point too. Emulation you just cant pay with wires or add >> a parallel port. > >Aha, I disagree. You can't get at the innards of the 6120 at all, >because it's a chip. If you want to get at the innards of an emulator >then you can, although how accurately the emulator models the logic of >the -8 might be an issue (my emulator doesn't model it at all, but >largely does its own thing). True, you can carry it with one hand and it does run os/8 rather than os/278. If I want to be in the innards of a CPU I hav e a real pdp-8 and a decent scope. I've yet to see a emulator that can let me see the r/m/w cycles of core on the scope. But I can add ports to a SB6120. If of course if you program a large CPLD or FPGA you can have your software verion of the chip and you can even get at the innards with your VHDL complier. No different from the 6120 as hardware but now you can play in software. Neither is wrong but if your designing a board that plug into a real PDP-8 and is software interactive then for all cases if (software emulation, parallel port kluge) sb6120, FPGA) our results will be "simulation" and at best does not have the feel, or actual dynamics of the electronic issues( termination, bus ringing, grounding and so on). >Adding a parallel port is easy - you've got one on your PC. Work out >what you want to talk to the parallel port, and graft on a bit of code >to do it. Dead easy. Sorry doesn't work when you need 12 bits, or Data break and the hardware is very code interactive. >Need more ports, or a smart-ish peripheral? Get one of those >microcontroller boards with a USB device port and a bunch of IO lines. >The Arduino Diecimila looks pretty good for this, although having more >than one UART would be nice. The UART talks to a generic USB-to-Serial >chip (FTDI, for those interested) and you've got an assortment of >digital IO, analogue input and PWM lines to play with, and a bunch of >timers and things. It presents to the PC as a serial port, and you >program it in C. I reckon with one of them and a bit of interfacing >hardware (level shifters and latches, mainly) I could drive most PDP-8 >peripherals (if I had any). If I wanted to build a PC for the task I'd use one. The original goal was to emulate or simulate in software the unique hardware for the pupose of writing new code that would run on the real (z80 powered) thing with that unique hardware. If I want to run an abstraction and I do on occasion then many of the sims are great for that. Most sims allow for good many of the available "peripherals" and thats fine if your running real hardware the same way or wishing you could. Allison

16 years, 7 months

Minimal CP-M SBC design

by ajp166＠bellatlantic.net

> >Subject: Re: Minimal CP-M SBC design > From: Ethan Dicks <ethan.dicks at usap.gov> > Date: Sun, 11 May 2008 13:01:31 +0000 > To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org> > Cc: General at icecube.southpole.usap.gov, > On-Topic Posts Only <cctech at classiccmp.org> > >On Sun, May 11, 2008 at 08:23:13AM -0400, Dave McGuire wrote: >> Well I wasn't talking about a diskless system...only one in which >> CP/M itself was in ROM. > >I personally find the idea intriguing, and I am about to cobble up >a system from (nearly) scratch. I used Kaypros and the like, back >in the day, and really won't miss floppies (not that there's an FDC >chip within 3000 miles I could slap on this thing, anyway). > >I don't mind the idea of stuffing "the OS" in ROM vs loading off >of removable media since I doubt I'll want to upgrade. I want to >run a few CP/M-80 programs, and that's about it. NOte It's not OS in rom, it's Rom as floppy replacement. CP/M load process for floppy is a booter load system tracks to ram.. The rom appaorach is booter loads system from ROM to ram. and once in ram you can overlay, alter, patch, extend as desired. >> >I still don't have the hang of this "vintage" thing yet, probably >> >because I'm vintage myself. Please forgive my density... >> >> I often suffer from the same problem. I think very few of us, even >> here, actually used stuff like CP/M and PDP-11s when they were >> considered current technology. > >I was a kid when S-100 machines were "in", but, as came up earlier >in this thread, I did hit the Osborne/Kaypro CP/M era. When I was an adult S100 was introduced. >I consider myself quite fortunate that I've gotten to program PDP-11s >on two different jobs right at the tail end of their heyday (I was 18-20 >at the time). I also consider myself fortunate that I was working at >a place that supported VAX/BSD customers in addition to our VAX/VMS >customers, so I was able to pick up some UNIX skills nearly 25 years >ago. When folks bandy about "All the World's a VAX", it really means >something to me (I learned C from K&R on an 11/750 running 4.1BSD, so >I _know_ how easy it is to write non-portable code). > >I do run things inemulation, but I also enjoy running things on real >iron. Right now, I have a modern Elf within reach, as well as an >SBC6120. The SBC6120 boots off of CF... no floppies, no 1/3 HP rotating >media, but there's still a real 12-bit processor on the board. I don't >consider that emulation in the slightest, even if my "disks" don't rotate. >OTOH, I also have, at home, "real" PDP-8s with real DEC-made disks; they >just aren't so portable as to be worth hauling down here. Same goes for >a CP/M machine - I'm working on something smaller than a princess phone. >Quite portable compared to an S-100 or an Osborne. Bob's SBC6120 is as close or better than a real 8e for playing with code. That s the point too. Emulation you just cant pay with wires or add a parallel port. >Just my take on why I mix classic CPUs with modern peripherals... runs >the original software, weighs a lot less. ;) and it can be faster too. A 64K z80 system that has a 32mb CF will do everthing the same as my S100 create with a Quantum D540(32mb) hard disk only it cant cause back pain, it's about as fast and the CF based machine can run on small batteries where the S100 crate can suck up a APS 1000VA UPS in short order (that has two 12V 7AH gell cells or ~168WH of power). Allison >-ethan > >-- >Ethan Dicks, A-333-S Current South Pole Weather at 11-May-2008 at 12:40 Z >South Pole Station >PSC 468 Box 400 Temp -79.6 F (-62.0 C) Windchill -108.3 F (-77.9 C) >APO AP 96598 Wind 5.8 kts Grid 42 Barometer 682.8 mb (10523 ft) > >Ethan.Dicks at usap.gov http://penguincentral.com/penguincentral.html

16 years, 7 months

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test-drb May 2008