Z80 anyone?
xanatos
Posts: 1,120
I have 10 of these loaded boards, which were working when removed from service... about 15 years ago. Now, I need the card cage they were occupying, and I want the cards to go to a good home. Each has a socketed Z80 CPU, plus uarts, uv eproms and other stuff. Any Z80 fans here? 
1024 x 576 - 132K
1024 x 576 - 108K
1024 x 576 - 125K
1024 x 576 - 115K
1024 x 576 - 138K
Comments
Don't know if you are prepeared to ship one to Finland or how I would pay for that.
What are they actually?
How much do you want for one or two of them?
Jeff
Bean
Amanda
I'll wait for Chris to chime in and then figure out postage and get back to everybody. In the meantime - those that wants 'em... please PM me with your shipping address.
FYI these were used to control HUGE - like the size of a VW - flatbed scanners that were used to send 300 lines-per-inch scans of the images on 16" x 30" platens back in the 1980s and early 90s. The scanners were on airbeds, which supported 700 lb granite block vibration-damping equipment bases, and had a massive 12-sided polygon mirror that created the scanning beam, along with huge "Field Flattening" lenses to compensate for the difference in focal length between the center and the edges of the scans. There were also acousto-optic modulators (which I also salvaged when these went out to pasture) that were responsible for making the corrections between the 12 different mirrors' slight variances from scan to scan.
All this stuff, including the PMTs, steppers, etc., were controlled by the Z80 boards pictured. They also interfaced to the TDMA Satellite system where we sent the images over what was Westar 5.
My how times have changed!
Addresses folks! :-)
Dave
Dave,
Looks like BS2PX are back in stock!!!!
If you want to send me all the Z80 boards, I'll take care of shipping them if you don't have the time. Seems I have a lot of time on my hands right now.
Jim
We can see some RAM and ROM on there, plus a counter timer chip, plus a dual UART.
Yea,
At first I thought they where 22/44 boards. I have cages for them. (22/44)
I'm really hoping we have enough horsepower in the P2 to do a full Z80 system in emulation. I've got an application where some inexpensive computers based on this could really be handy.
BTW, the N8VEM project is pretty cool too.
Jeff
I need to be able to run Wordstar, load/save documents from SD using a keyboard and VGA monitor.
Jeff
Ah ha, you have not been paying attention over the years then;)
The ZiCog Z80 emulator has been running CP/M 2.2 and WordStar and BDSC and a lot of other stuff for some years now. Then there is the qz80 emulator from PullMoll which does all of that and more.
http://forums.parallax.com/showthread.php/110804-ZiCog-a-Zilog-Z80-emulator-in-1-Cog
Sorry I can't find PullMoll's threads just now.
Just now, after a long hiatus I'm trying get back into ZiCog. It needs making easy to use, documentation and getting ready fro Prop II.
Jeff
Ah, you hit the nail on the head there.
As far as I know if you want 64K of memory for your Propeller CP/M system then you need some external RAM. And all such external RAM solutions are custom.
Cluso and I were happy cruising along on his TriBlade and RamBlade solutions. I believe DrAcula has other solutions.
Minimum requirement is:
1) A single Propeller.
2) 64K external RAM.
3) SD card.
Given the normal serial port on your programming pins.
Item 3) is a pretty standardized set up
Item 2) is a bit more tricky and may require a RAM driver being created for whatever solution you have.
This is most closer to reality for my applicaiton that I thought..
Quick overview on this website http://smarthome.jigsy.com/propeller
That is with latches and a parallel ram. Frogger and Space Invaders and Pacman are all running on Pullmoll's qz80 emulation.
Heater says that his Z80 emulation may not be quite perfect? After spending some time deep inside various Z80 emulations written in C/Basic etc, maybe there are some insights there that could be useful? I think there is an exerciser program written for the Spectrum emulator.
I have been designing some new boards. I want a board that can run most of the things I have worked on over the last few years - a simple propeller board plus all the complex stuff. Wish list:
* Keyboard
* SD card - with several different footprints as sometimes module PCBs on ebay are cheaper than SD sockets
* TV
* VGA
* Sound
* Serial port
* IC2 breakout with multiple voltages, for talking to I2C digital and analog IO chips
* On board serial ram for running large C programs
* Touchscreen (these are getting cheaper every month)
* Some spare propeller pins brought to a header
* 32 digital I/O pins - High, Low and HiZ
The above is great, but let's tempt heater a bit here. Let's also put a Z80 on the board, with the challenge to take the Zicog and run it from cache serial ram and replace most of the chips on the attached schematic *grin*
Ok, this board also has a real Z80 on it. I'm working through the code to boot it up at the moment. I think it could also be a stepping stone to getting a perfect Z80 emulation working. And I say perfect, because heater (correct me if I'm wrong) says that his emulation has not been 100% tested, and Pullmoll's seemed perfect for CP/M but it fell over when trying to run MP/M. So, for those with OCD, the Z80 emulation isn't quite there yet
What this board could do is enable a comparison between a real Z80 and an emulation. Run the emulation in the serial ram chip attached to P0-P3. You could load up a test program on the real Z80 chip and then compare results with an emulation. I suspect there could be the odd bug, because some of the DAA code I've seen in various emulations seems a lot longer than some other emulations.
Just to explain this schematic a little, two MCP23017 chips replace a physical parallel eeprom, and as a bonus, can also handle bank switching. Each bank of 64k has no direct comms to other banks, which is different to every other Z80 circuit out there, but it saves a few chips to send a message to a propeller saying "change banks". Messages can also be sent saying "move a block of data between banks". The catch is that the MCP23017 chips are slower because they are serial, so there is also an SPI interface between the Z80 and propeller. Data can come off the SD card and be transferred into the Z80 and the speed should be just a little slower than SD comms. Possibly similar if we push the clock frequency of the Z80 from 4Mhz to 10Mhz.
Of course, if you want a real Z80 chip, talk to xanatos!
I'm going to reply to this in the ZiCog thread. Hang on a bit.
I have addresses from OBC, ajward, heater and Publison. My project installs tomorrow, thank God, and after that I'll be getting things caught up on other fronts. If you're wanting a board - I'll need your address this week. I'll have shipping costs posted after send off the first one to Publison, who gets free shipping for helping me out with the BS2px crisis! :-)
Dave
Thanks Dave,
That's very nice of you!
Jim
-Tor
Turns out that in that code there is detection for whether it is running on 8080 or Z80. If Z80 is detected then at least the BIOS makes use of the block move instructions. I discovered a bug in that whilst swapping back and forth from 8080 to Z80 emulation and my patch is now in SIMH AltairZ80.
What that says about MP/M I have no idea.
So, if we replace the Z80 emulator with an 8080 emulator MP/M may run better? If indeed the problem is in the BIOS trying to execute Z80 instructions. Maybe we could exercise the BIOS itself stand-alone and try to figure out where the problem is?
-Tor
I think you might be on to something re: MP/M and Z80.
I presume MP/M has some kind of timer tick interrupt. Currently ZiCog has no support for interrupts (except software interrupts). How qz80 handles this I have no idea.
Bean,
You have a good memory! Years ago I was totally into the Z80 and spent 1990-2000 making all kinds of cool things using them including some commercial endeavors. Sadly though in 2000 in an attempt to force myself to start picking up new technology and get out of my comfort/safe zone I sold all my Z80-related hardware via the usenet newsgroups and donated the books to the local library. The Z80 has been and will always be my friend, err, ahem, my favorite CPU platform, but I don't have anything Z80 related anymore.
I did the same thing with my Commodore stuff when Commodore went under and have been kicking myself since then. I miss both platforms (Z80 & C=).
What kind of Commodore stuff are you interested in? I've been adopting C= hardware for years and the herd could be thinned a little.
Jeff
Jeff,
I used to be the go-to guy in Schenectady/Albany New York area for Comodore stuff, repairs, mods, etc. But in 2000 I gave all my hardware away to a Commodore User Group that has since vanished and every once in awhile I get the itch to play around, but at the prices they're going for on eBay for a working unit I just can't do it. I've offered to trade hardware too, but it's amazing how much a C=64 is worth to some.
P.S. - I liked your original avatar with the butterknife better.
I've decided to quit starring at that huge shelf in my shop with a bunch of systems that are just collecting dust. It's time to either get them up and running or find homes for them...
I put the Sun Spac 10 on Ebay tonight (being one of the units I haven't touched in 10 years.) As I pull machines off the shelf and get them tested, (might take me a bit) I'll make sure I set aside a C=64 for you.
If you want real fun from it, get a uIEC adapter from my friend Jim Brain. In lue of that, there was a neat C64 Tape project on here some time ago.
Jeff