Dracblade SBC with Catalina C, PropBasic, CP/M, MP/M, TRS80, wireless network,

Dr_Acula · 2009-12-01 03:33

This board is a single propeller emulation of the Z80 computer running CP/M. 8x8Mb hard drives on an SD card, two serial ports, 512k of ram, LCD display, VGA display, keyboard and onboard 5V/3V switching power supplies.

The board is a fusion of heater's Zicog, Cluso's triblade, Vince Briel's Pocketerm, Oldbitcollector's VT100 terminal, Brad's BST and Peter Schorn's Altair SIMH. Complete writeup is at www.smarthome.viviti.com/propeller including schematics and code.

Current project is to build a layer of wireless software protocols in Spin sitting underneath CP/M that will allow networking and file transfers.

Compile and download with Brads Spin Tool www.fnarfbargle.com/bst/bstc/Latest/ as the standard propeller tool can't compile the #ifdefs used throughout this code

Enjoy!

Addit 19th January, 2009 - attached Build instructions PDF.

Addit 12th Feb, latest code (works for all versions of the board)

Addit 8th March new Spin source code, 150 longs shorter.

Addit 10th March, 456 longs shorter. Creating free space in preparation for the new zicog that will implement all the Z80 opcodes.

Addit 14th March - merged with the latest version of the Zicog so now using the same code (with #ifdefs) as the triblade and other zicog emulations

Addit 20th March - changed string("mystring",0) to string("mystring",1) in two places as per parallax syntax changes

Addit 30th March - major sd card access and ram rewrite by hairymnstr

Radio modules www.sureelectronics.net/goods.php?id=1053

Addit 13th April, back to 28th March SD card code while bugs sorted out. Also added banked memory so can run two CP/M machines on the one board. See posts 13th April for download.

Addit 28th April 2010, code upgraded to MP/M which can run true multiusers. The code has been written by pullmoll and the download is on the first page http://forums.parallax.com/showthread.php?p=897549. This code does everything the code above does, but it is faster, more flexible (eg baud rates for file transfers 4x faster) and the code can use single user CP/M or multiuser MP/M (MP/M is run as a program from CP/M). The multiuser environment is a stepping stone towards true wireless networking between multiple boards, with packet encoding and decoding being run in one of the MP/M users.

May 5th - See NASCOM thread for a NASCOM emulation (a great selection of games) and TRS80 thread

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Post Edited (Dr_Acula) : 5/5/2010 1:09:07 AM GMT

Cluso99 · 2009-12-01 03:38

Congratulations James

I noticed yesterday a thread mentioning using a single pin for clock and data using a RC delays. I am ken to see if this will work with Peter's LCDs. Also wonder if we can use this for the PS2 keyboard. Of course it will be slower, but might be good enough for what we want in a simple LCD interface.

I will email you a release candidate software as soon as I can so you can get the DracBlade bits for a V2.1 release quickly.

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Links to other interesting threads:

· Home of the MultiBladeProps: TriBlade,·RamBlade,·SixBlade, website
· Single Board Computer:·3 Propeller ICs·and a·TriBladeProp board (ZiCog Z80 Emulator)
· Prop Tools under Development or Completed (Index)
· Emulators: CPUs Z80 etc; Micros Altair etc;· Terminals·VT100 etc; (Index) ZiCog (Z80) , MoCog (6809)
· Search the Propeller forums·(uses advanced Google search)
My cruising website is: ·www.bluemagic.biz·· MultiBladeProp is: www.bluemagic.biz/cluso.htm

jazzed · 2009-12-01 03:55

A little small for an Osborne [noparse]:)[/noparse] Nice work DR.A. Really. Congrats.

Dr_Acula · 2009-12-01 05:21

Re "A little small for an Osborne [noparse]:)[/noparse]"

I suppose I could always put it in an old PC case. With some lead weights to get it up to the old 'laptop' standard of 25kg. And to think people took those computers on planes!

Getting close to a protocol for networking. Needs to have data packets wrapped up with something like
start:#source:#destination:#bytes:databytes...:end

I've got some 10mW wireless modules that go several kilometres with 256 byte buffers, but a lot only have 32 byte buffers. So for more compatibility with multiple brands, maybe need to use 32 bytes max. One positive about these modules is they have onboard micros so checksums are not needed - the data tends to go through 100% reliably up to a certain range then fails to go through at all. No data is probably better than corrupted data.

I think if this layer sits underneath the operating system it only would feed through bytes that are specifically for that board. I've had xmodem working ok but only between two boards. The challenge is to have three boards or more and persuade the ones not in the conversation to be quiet for a moment.

Also a link needs to die if it has been inactive for a while. Hmm, I need some sort of timer ticking away in a cog somehow. Aargh, no cogs left. Might have to patch the keyboard driver or something.

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Cluso99 · 2009-12-01 05:58

Re "A little small for an Osborne [noparse]:)[/noparse]"

I remember when the Taiwan PC clones were first available, they came in smaller pc cases. Most thought that something was missing, so the big PC cases won out for such a long time, just filled with air !

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Links to other interesting threads:

· Home of the MultiBladeProps: TriBlade,·RamBlade,·SixBlade, website
· Single Board Computer:·3 Propeller ICs·and a·TriBladeProp board (ZiCog Z80 Emulator)
· Prop Tools under Development or Completed (Index)
· Emulators: CPUs Z80 etc; Micros Altair etc;· Terminals·VT100 etc; (Index) ZiCog (Z80) , MoCog (6809)
· Search the Propeller forums·(uses advanced Google search)
My cruising website is: ·www.bluemagic.biz·· MultiBladeProp is: www.bluemagic.biz/cluso.htm

heater · 2009-12-01 07:00

Dr_A. That is a great board. You have created almost exactly the home for ZiCog that I had in mind when I started all those months (years) ago. Well, except much better. I would have hacked it together on a home etched board using old 32K SRAMS and bits I have in my junk box.

And a very nice write up on your smarthome page.

One little detail, in the write up you mention using standard disk images from SIMH. This is true except for the drive A: boot disk that needs our customized CBIOS on the boot sectors.

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TonyWaite · 2009-12-01 07:53

Very, very smart. It looks like a powerful system to me!

Toby Seckshund · 2009-12-01 08:28

Dr_A

Next is the SM version,·inside the KBD ( work disguise ).

Then there will be somebody who recons that they could get it int the KBD's plug ...

PS. Is this a sort of settled version? I know you were hinting of a few HW changes.

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Post Edited (Toby Seckshund) : 12/1/2009 8:37:16 AM GMT

heater · 2009-12-01 08:47

Toby: You can now get a Linux running computer inside an RJ45 socket www.lantronix.com/device-networking/embedded-device-servers/xport-pro.html. So no problem.

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Baggers · 2009-12-01 09:26

Looks excellent Dr_Acula [noparse]:D[/noparse] congrats!

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Dr_Acula · 2009-12-01 11:18

Thanks for all the comments.

Re "PS. Is this a sort of settled version? I know you were hinting of a few HW changes."

Yes, the hardware is stable. The addons like radio all are plug in separate modules that go into the D9 serial ports.

One thing I'm wondering about is maybe TV resistors instead of VGA, but I think I'll stick with VGA as the monitors are free. There is the little prototyping area for extra circuits.

Also - I guess expanding the I2C bus for A-D chips. Though a picaxe chip gives you a lot of A-Ds and I/O pins for only a few dollars and that can also go on a serial port so again it is an add-on rather than a change to the hardware.

So these are all add-on projects and the hardware is stable. Maybe you could change things eg the 5V switcher is a TO220 case but the 3V switcher is a DIP8. They were the cheapest options from Futurlec.

Hmm - it could go to maybe 1/4 the size with surface mount and a uSD instead of standard SD. But I'll leave shrinking the circuit to experts like Cluso.

Thanks for the note from heater re the customised drive A. I missed that.

Re 32k rams, they were tempting and indeed it would be possible as you could drop in 5V ones from the junkbox, put 8 x1k resistors in the data lines and run all the latches on 5V. But the single 512k ram chip from future electronics comes out cheaper than two 32k ram chips from futurlec. And the Alliance chip is 55ns and that is faster than a lot of the older chips. If you have a slower chip you would need an extra NOP - which you can't do as there are no longs left in the Zicog. Plus I think there will be other uses for the extra 448k. Banked CP/M. A big buffer for a bittorrent file before it is sent to CP/M. Ram disk. LMM for native C and Basic for those that don't need CP/M. Especially since the drivers are written and are as simple as calling a routine to read or write a block to memory.

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Cluso99 · 2009-12-01 11:36

By substituting the resistor values and joining 2 resistor pairs you have TV from VGA

So it is only required to allow a solder bridge and pads for the RCA TV connector under the VGA connector - a simple solution.

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Links to other interesting threads:

· Home of the MultiBladeProps: TriBlade,·RamBlade,·SixBlade, website
· Single Board Computer:·3 Propeller ICs·and a·TriBladeProp board (ZiCog Z80 Emulator)
· Prop Tools under Development or Completed (Index)
· Emulators: CPUs Z80 etc; Micros Altair etc;· Terminals·VT100 etc; (Index) ZiCog (Z80) , MoCog (6809)
· Search the Propeller forums·(uses advanced Google search)
My cruising website is: ·www.bluemagic.biz·· MultiBladeProp is: www.bluemagic.biz/cluso.htm

Mike Huselton · 2009-12-01 11:39

A thing of beauty - honestly. I am thrilled to be in the company of creative individuals like you.

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Dr_Acula · 2009-12-01 11:48

No way cluso?! Too easy. Thanks++ for the hint. I've got this nifty 7" TV screen I need to try out. If that works then version 3 will have a RCA socket.

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Toby Seckshund · 2009-12-01 12:32

I had a portable·DVD player on order ready for the "Blades" (X-Sound / Elonex) but it is only NTSC. Ok for Props but I was trying to wangle it via work, so PAL obligatory, Hey-Ho.

Heater,···· Yes I saw those a while back, next they will be complaining about the size of the RJ45.

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Humanoido · 2009-12-01 12:56

This project is absolutely fantastic and superbly accomplished!

humanoido

Bill Henning · 2009-12-01 15:25

Very nice!

Dr_Acula said...
This board is a single propeller emulation of the Z80 computer running CP/M. 8x8Mb hard drives on an SD card, two serial ports, 512k of ram, LCD display, VGA display, keyboard and onboard 5V/3V switching power supplies.

The board is a fusion of heater's Zicog, Cluso's triblade, Vince Briel's Pocketerm, Oldbitcollector's VT100 terminal and Peter Schorn's Altair SIMH. Complete writeup is at www.smarthome.viviti.com/propeller

Current project is to build a layer of wireless software protocols in Spin sitting underneath CP/M that will allow networking and file transfers.

Enjoy!

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Oldbitcollector (Jeff) · 2009-12-01 16:12

Cluso99 said...
By substituting the resistor values and joining 2 resistor pairs you have TV from VGA
So it is only required to allow a solder bridge and pads for the RCA TV connector under the VGA connector - a simple solution.

Couldn't an adapter of some kind be made with could plug into the existing VGA head?
I'm pretty sure my values are wrong, (or impossible) but take a look at the attached...

OBC

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Post Edited (Oldbitcollector) : 12/1/2009 4:43:45 PM GMT

Toby Seckshund · 2009-12-01 20:09

Dr_A

On the original cct you chose 74hc373s, but changed to the edge '374s, was this for a technical reason or "because you had some"? I've got a load of '573s here and could use before the '574s get ordered. I would like to get a fully chipped version going before attempting a CPLD.

JUST NOTICED IT'S THE FALLING EDGE THAT LATCHES NOT THE RISING

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Post Edited (Toby Seckshund) : 12/1/2009 8:22:23 PM GMT

Dr_Acula · 2009-12-01 22:13

HC374s latch on the rising edge as you say, and the polarity of the pulses is HLH which is set by the 138 which in turn is set by the /RD and /WR on the memory. You can't use inverters to go LHL because they add too much delay. Indeed, even the delay going into the gate of the HC138 to the output is adding one NOP in the code. (and if you look at the internals of the 138 the gate is half way through the path through the chip. (Cluso has no NOP as there is no delay going through any chips)).

Similar to you, I've got hundreds of HC373s and no HC374s. 37 vs 57 - I'd say 57 is easier to work with on a breadboard. On a PCB with an autorouter it probably doesn't matter.

CPLD sounds interesting. You want the delay as short as possible, so it would be worth thinking of the minimum number of gates the signal has to go through, which might end up being a design that has more gates but shorter signal paths.

Re a VGA to RCA dongle, that sounds interesting. I guess need to get some compact D15 plugs (and sockets). Not everyone sells them but Future Electronics who do the ram chip do sell them. They also do the inductors (which need to be >=1 Amp, ie a low DC resistance). There might be a supplier out there that could do all the parts in one order - maybe Digikey?

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Post Edited (Dr_Acula) : 12/1/2009 10:47:35 PM GMT

Toby Seckshund · 2009-12-01 22:35

The low resistance inductors tend towards toroids rather than bobins.

Delays, NOPS, they are just a completeness of the nosalga. At least they are not hundreds of nS. Like Heater I have a bucket of 32Ks that my past reverence will not allow me to chuck out, 32KB ram on my, dear lamented Nas, would have been a couple of months salary. The 512K used on the blades is fast, cheap and tolerent, always a bonus.

So off to order latches, sd cards and its socket.

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Mike Huselton · 2009-12-02 02:34

Dr. Acula,

Thanks for the ZiCog/Dracblade Download. This is what I was talking about when I referred to a "clean slate" to start with.

BTW, an engineer and I cooked up a home automation system in 1980 that used TTL logic.
It worked nicely as a Proof Of Concept. However I left Memphis shortly thereafter to pursue a career in Computer Software Design in Atlanta.

The rest is an erratic history of great accomplishment and failure (curse you, IBM!)
But the journey was worth it: 3 years in Sydney, 4 years in Sweden, 2 years in Cologne.

Thanks again...

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JMH

Post Edited (Mike Huselton) : 12/2/2009 4:34:42 AM GMT

Cluso99 · 2009-12-02 03:14

OBC: Love your concept of an adapter as it could be wired within a DB15 shell plug. However, aren't your values incorrect???

240R + 820R = 1K06···· (1K1)··· ok
240R + 560R = 800R··· (560R)·· 240R + 330R = 570R·
470R·········· = 470R··· (270R)·· requires a parallel resistor which is not possible externally

So, my question is... do your values work because it is a similar divider just shifted above ground??? Otherwise,·might it be possible to change the pins in the TV driver to make your idea work??? I would really like to use your idea - in fact both ideas could be used together.

My idea was an alternative (not either/or) using a dual footprint on the pcb. The ground mounting pin on the VGA would be common, and the Video (TV) pin would be an extra hole, with a track to pin 2 of the VGA. The by using alternate value resistors and a link in pins 1-2 of the VGA a TV (composite video) could be used. See dwg attached with changes in red.

attachment.php?attachmentid=65510

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Links to other interesting threads:

· Home of the MultiBladeProps: TriBlade,·RamBlade,·SixBlade, website
· Single Board Computer:·3 Propeller ICs·and a·TriBladeProp board (ZiCog Z80 Emulator)
· Prop Tools under Development or Completed (Index)
· Emulators: CPUs Z80 etc; Micros Altair etc;· Terminals·VT100 etc; (Index) ZiCog (Z80) , MoCog (6809)
· Search the Propeller forums·(uses advanced Google search)
My cruising website is: ·www.bluemagic.biz·· MultiBladeProp is: www.bluemagic.biz/cluso.htm

Post Edited (Cluso99) : 12/2/2009 3:19:38 AM GMT

Dr_Acula · 2009-12-02 05:04

That looks pretty straightforward. Question - what is the "aural subcarrier"? Is that resistor needed, or do you only need three resistors?

Re the resistor values, if that is a 3 bit D/A then the values on the demo board are not quite 1:2:4 anyway. It probably doesn't matter especially if the colors are white on blue or green on black. With the E12 series, I wonder what the closest value are? Maybe 470R, then two in parallel to halve the resistance, and two in series to double it? I might try 1.2k, 560R and 270R when I get home, because I have those in the parts drawer.

Hmm - if you only need 3 lines to drive TV, that leaves 5 pins free. What could we do with those? Another couple of serial ports. Some analog I/O. Audio in and audio out. Looks like I need another board soldered up for testing purposes...

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potatohead · 2009-12-02 05:13

You only need the three resistors.

The 4th is for audio, or S-video signal, both of which are configurable for start_pin+3

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Cluso99 · 2009-12-02 06:10

Or 2 TVs and a keyboard = 8 pins. BTW, you can always use the 1-pin TV !!

How about using the 4 pin 3.5mm stereo connector - iPod and Nokia have breakout cables to RCA but the gnd & video swaps (cheap on eBay) so video + stereo.
Digikey
CP-43514-ND CONN 3.5MM AUDIO JACK 4 COND PCB
CP-43514SJCT-ND CONN AUDIO JACK 3.5MM 4COND SMD

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Links to other interesting threads:

· Home of the MultiBladeProps: TriBlade,·RamBlade,·SixBlade, website
· Single Board Computer:·3 Propeller ICs·and a·TriBladeProp board (ZiCog Z80 Emulator)
· Prop Tools under Development or Completed (Index)
· Emulators: CPUs Z80 etc; Micros Altair etc;· Terminals·VT100 etc; (Index) ZiCog (Z80) , MoCog (6809)
· Search the Propeller forums·(uses advanced Google search)
My cruising website is: ·www.bluemagic.biz·· MultiBladeProp is: www.bluemagic.biz/cluso.htm

Toby Seckshund · 2009-12-02 08:44

Dr_A

I have always ended up using 1K2,560 and 270, without any problems. Even when I plan to use 1k1 we don't have any or I leave then at work. Very few of the old computers gave 0.3V sync with 0.7V pic and none gave proper SC/H to keep down the "chroma-crawl" artifacts.

I have found that my 5MHz Xtal on the "demo board" runs slightly low freq. If the constant is quoted to this lower freq then the background chroma beating is much more bearable ( perhaps it is the "more lsb 1's the more jitter" thing). I did try using 4.43 (etc) ·xtals to see if the Prop's life could be simplified but I think that the minimum 80MHz wasn't reached

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Dr_Acula · 2009-12-02 13:01

Just soldered up board #3 configured for TV. The display I'm using is a 3" TV LCD and it looks fairly ok when fed a picture from a 3 megapixel camera and/or DVD player. I tried feeding it the output from TV_terminal_demo. spin, but the characters are not all that crisp. They are all there ok and in the right colors and are legible, but not as sharp as VGA. I suspect that is a function of the display more than anything. Also counting the letters it is only a 40 column display.

I wonder if some of those 320x240 graphics LCDs might be sharper? Different driver of course.

I just inherited two more vga LCD screens today for free (everyone is going for widescreen 22" VGA nowadays) so they can go with the three freebie CRT VGA monitors. Going to need a new shed soon...

I'll probably stick with VGA and the text/graphics LCDs rather than TV. But at least the experiment does work and you can drop in those three resistors and run TV. I think that is enough of a reason to put a RCA socket on the next boards.

I do have one more experiment - on a real TV, but first I have to get 'her indoors' off the TV.

PS had three PMs today requesting boards. Hopefully shipping won't be too long from Australia to the US.

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Humanoido · 2009-12-03 00:32

I agree, the RCA TV socket will be useful for running direct video, ntsc format here. I would rather purpose out the vga ports for another use.

Dr_Acula · 2009-12-03 00:40

Thanks to the 4 people who ordered boards in the last 24h. On their way now to the USA.

I'm trying to juggle a waiting room of patients at the moment and the interest in this board. So this is a quick post, but thanks ++ to the person who overpaid to fund beverages for the next zicog conference. I've got real names for the addresses so I'm not sure how they match up with names on the forum.

I've 4 boards left. I could get more made exactly as they are or wait a few days when I have a moment and add some features to the board. New things to add:
1) RCA socket and the four resistors for TV (could double up with VGA ones but I think it is simpler to have seperate pads).
2) Bring out the I2C to header pads. I don't have time to buy I2C A/Ds and test etc but I think a header allows expansion.
3) I might bring out the 8 VGA pins to pads. For those that are using TV or a board with just the 20x4 LCD these could be used for other things.

Plus other things that might come up in the next couple of days. Suggestions most welcome.

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heater · 2009-12-03 02:04

Dr_A, Any chance of squeezing a real-time clock on there? CP/M 3 would like that.

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For me, the past is not over yet.

Dracblade SBC with Catalina C, PropBasic, CP/M, MP/M, TRS80, wireless network,

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