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JonB
January 22nd, 2017, 07:24 AM
Hi

I've just completed IDE drivers and a prototype interface for the Amstrad PCW range of computers. CPM Plus. If you are interested, more info here : http://www.cpcwiki.eu/forum/nc100-nc200-pcw-pda600/who-wants-ide-drives-on-the-pcw/

Cheers
JonB

Chuck(G)
January 22nd, 2017, 08:30 AM
That's pretty cool, Jon. You don't see the PCWs discussed much here. I have a Joyce myself.

JonB
January 22nd, 2017, 09:19 AM
Then you're going to want one.

Chuck(G)
January 22nd, 2017, 09:34 AM
No, not really, Jon. My Joyce has been stashed away for years. It's got the full 512K, but with no printer or comm, it's not very useful.

AlexC
January 22nd, 2017, 10:58 AM
Nice work. I have a serial/parallel module for one of my PCWs but haven't yet built the modified serial cable to connect it to a PC. I'm planning to fit a 3.5-inch floppy drive to the other one. Was there enough software written for these machines to make a hard drive useful and/or would most of the software run that way?

Chuck(G)
January 22nd, 2017, 11:36 AM
Be very careful when converting to 3.5" drives on these old CF 3.0" models. The +5 and +12 on the drive connector are swapped from what they are on 3.5" drives. Unless you modify them, you'll likely toast the 3.5" unit.

AlexC
January 22nd, 2017, 12:18 PM
Yes, I've read about that. I have a few spare drives but hopefully I won't toast any of them.

JonB
January 22nd, 2017, 12:26 PM
Be very careful when converting to 3.5" drives on these old CF 3.0" models. The +5 and +12 on the drive connector are swapped from what they are on 3.5" drives. Unless you modify them, you'll likely toast the 3.5" unit.

Too late! I toasted a Sony 3.5" drive already. :(

JonB
January 22nd, 2017, 12:29 PM
That's pretty cool, Jon. You don't see the PCWs discussed much here. I have a Joyce myself.

Thanks for the compliment, Chuck.

PCWs don't get discussed much anywhere, seemingly. Not even on the CPCWiki forum. Which is a pity because they are very cheap (in the UK at least: I bought one for 15 last year with printer and AMX mouse) and can be very accessible if you want to learn about CP/M Plus. Sure, the screens are a bit naff (hmmm, keyboards too) and they are awkward to transfer stuff too, but for a basic machine the bang per buck is hard to argue with.

Chuck(G)
January 22nd, 2017, 12:31 PM
Well, don't say you weren't warned--I first posted on this years ago.

For what it's worth, if you've got a single-sided boot version of CP/M 3, all it takes to make it double-sided is a one-byte change in the boot sector. I posted on that also.

SteveH
January 22nd, 2017, 12:54 PM
Nice one Jon :D

Now, what would be really cool is if you managed to get James to design a lo-tech PCB version of this using a shim socket to connect directly to the Z80. I'd have one straight away.

JonB
January 22nd, 2017, 09:41 PM
I'm going to do that myself. I already have the design (it's not the same as the LoTech board, but based on its predecessor).

glitch
January 23rd, 2017, 06:30 AM
Neat! Been meaning to design something to go on the expansion port on my PCW.

jonhales
January 23rd, 2017, 08:23 AM
Hi, Jon

This looks very useful - many thanks for your efforts. Please add one to the number of PCW users interested in making one of these. I'd prefer a PCB and BOM; no preference for the way it fits.

Also interested in your video mod - have you posted about that?

JH

JonB
January 24th, 2017, 09:19 AM
No, but it's very straightforward and someone else's design. I did a schematic on strip board. Will post it tomorrow.

SteveH
January 25th, 2017, 12:49 PM
Hi Jon, Any pics or schematics yet?

jaquinn
January 25th, 2017, 01:41 PM
That is great work. For many years this has been on my "To Do" list but never got there, particularly the driver development. Really keen to build one or do an extended version of the board that includes an RS-232 port. That would make the 8256 pretty usable.

When you say it was based on the predecessor to the Lo-Tech board are you meaning my original TRS-80 design at http://www.qsl.net/zl1wjq/trside1.htm

JonB
January 26th, 2017, 01:21 AM
Sorry, asleep at the wheel...

35729

This is the latest iteration of the board, which uses just two ICs and a handful of discrete components. But please note, it's not tested yet as I have no materials on hand to build a prototype. I've ordered the stuff from China but you know how long that can take.

uIDE Universal IDE Apdapter Features:


LEDs for Power and drive activity.
Selectable I/O base address via jumpers (the current PCW driver's case address is C8h).
Z80 shim connector - plugs into a shim card such as this one: https://www.sellmyretro.com/offer/details/21802 - but I'm going to offer one too.
Will require a separate adapter board instead of a Z80 shim if you need to connect it to the PCW external expansion port, which I will design.
Z80 shim input scheme means you could build a generic bus and connect additional devices (such as RS232, mouse, parallel, GPIO, etc).
Should be capable of supporting two IDE devices (Master and Slave) - but not on the PCW (yet - it's a driver thing).



That last point is particularly interesting (and only just occurred to me). If I move the input connector to the edge of the board, you could use a 90 degree header and plug it into a ribbon cable with multiple IDC connectors, which then becomes your bus. At that point, it's a simple matter to design other cards like RS232 to plug into the same bus. Oh dear, where is this leading..? :rolleyes:

@jaquinn: You could (with the shim) connect it to any of your Z80 machines (Kaypro, Northstar, etc) and run it with the right driver. I already wrote a driver suite (including formatting, drive mapping, slave drive support) for Lifeboat CP/M 2.2 on the TRS-80 Model II and this could be ported to other CP/M 2.2 variants with a moderate amount of effort.

JonB
January 26th, 2017, 02:00 AM
Also interested in your video mod - have you posted about that?
JH

It is an implementation of a design I found on the internet (there are several, but this was the simplest) on strip board:

35730

(The layout is my own work but not the design of the original circuit.)

Key as follows:


Grey horizontal lines are the stripboard tracks.
Coloured lines are signal paths. Where they are straight vertical they join the horizontal tracks. Where we need to jump over a strip board track they are bridged.
Small dotted circle: Strip board track break (use a drill but to cut the track).
Large dotted circle: Capacitor (C1 = 100uF, C2 = 47uF). Note, C1 is labelled incorrectly (says "C2").
U1 is 74LS00 quad 2 input NAND.
R1 is 1k, 1/4w
VR1 is 1k variable (although I used a 10K variable in mine and it still works).
Scart pin 20 is "Composite Video".
Scart pin 11 is "Green". But don't worry, it seems to come up as white on my monitor.
The vertical red dotted line is a component side jumper between tracks 2 and 10 (counting from top to bottom.


It is designed to plug directly into the PCW9512 video header, component side up, with the card overhanging the rear of the machine. The purpose was to keep the signal paths as short as possible, because the prototype (built on breadboard with jumpers) generated lots of screen noise. But I found that I didn't have the right connector so it ended up component side down, pointing inboard - a bit of a bodge. JP1, the +5v pin, is connected to the motherboard's +5v input using a probe clip. You could just as easily wire it to the +5v line on the expansion port by soldering a header pin to the via just inboard of the edge connector. Then a short jumper wire from there to JP1.

Please be aware it is untested on the PCW8256. The wires coming from the 8000 series monitor board are not the same colours as the 9512's, but the service manual checks out (Sync / GND / Video / GND) so you should be OK. If in doubt, match the orientation of the blue video connector on the 8256 motherboard by looking for the two ground pins (you can't miss them, they have fatter traces than the other pins and are clearly connected together). And be careful of the video circuit, there are dangerous voltages lurking around, even when the computer is switched off.

SteveH
January 26th, 2017, 03:45 AM
Hi Jon, Care to share your schematic? I'd like to try it (or something like) on stripboard for a non Amstrad machine (my LSI M-Three (http://www.vcfed.org/forum/showthread.php?49057-1982-British-built-LSI-M-THREE-computer-restoration-project))

JonB
January 26th, 2017, 06:53 AM
Hi Jon, Care to share your schematic? I'd like to try it (or something like) on stripboard for a non Amstrad machine (my LSI M-Three (http://www.vcfed.org/forum/showthread.php?49057-1982-British-built-LSI-M-THREE-computer-restoration-project))

I'm afraid not, because I don't know if it actually works, yet:


But please note, it's not tested yet as I have no materials on hand to build a prototype.

That sort of thing (it not working) could put a dent in your day.. and stripboard working takes a long time (as I found out when I built that video mod).


..my LSI M-Three (http://www.vcfed.org/forum/showthread.php?49057-1982-British-built-LSI-M-THREE-computer-restoration-project)

Oh THAT one.. I remember seeing the screen (it was on eBay, right?) and thinking no one would buy it. Well, good for you! And the restoration looks right classy. I assume it's a Z80 CP/M 2.2 machine. I have a TRS80 Model II with SA800 drive which I love, because it sounds like a real computer (whirr whirr clunk clunk), plus a second SA801 (double sided) drive sitting on a shelf waiting to be fixed. It seems unable to seek to 0, but if you set it there manually it works. Odd. Yes, you can definitely use my card with it (and the Z80 shim), and let me tell you - CP/M 2.2 with hard drives is dead cool. If you want to know what to expect from my driver suite, check out the readme.txt which I copied into the first post here:

http://www.vcfed.org/forum/showthread.php?55487-TRS-80-Model-II-Lifeboat-CP-M-LoTech-IDE-Adapter-Extended-Driver-v1-9

Don't be put off by the thread being in the Tandy forum, everything in the xdriver package is generic CP/M 2.2 and will be in any variant I produce for other CP/M 2.2 machines. Including your M-Three if you want it and are willing to assist me in finding out about your BIOS.

SteveH
January 26th, 2017, 09:45 AM
I'm afraid not, because I don't know if it actually works, yet...

Fair enough. I can wait until it's proven working, or maybe assist where possible.



Oh THAT one.. I remember seeing the screen (it was on eBay, right?) and thinking no one would buy it. Well, good for you! And the restoration looks right classy. I assume it's a Z80 CP/M 2.2 machine..
<snip>
...everything in the xdriver package is generic CP/M 2.2 and will be in any variant I produce for other CP/M 2.2 machines. Including your M-Three if you want it and are willing to assist me in finding out about your BIOS.

Yep, it was on eBay. It needed a thorough clean inside and out, plus reparing the screen cataracts and re-capping the power supply. And as it didn't come with any software I disassembled and documented the firmware prom in order to write my own monitor prom for it - details of which Al kindly uploaded to bitsavers (http://bitsavers.trailing-edge.com/bits/LsiComputers/LSI_M3/Firmware/) for me. I've since written a CP/M 2.2 CBIOS for it, patched it with ZCPR and have it running with a HxC floppy emulator. I'm in the process of re-writing the utility programs the operations manual (http://bitsavers.trailing-edge.com/pdf/lsiComputers/LSI_Computers_M3_Operations_Manual.pdf) said originally came with it.

35731

What I'd really like to do with my LSI M-Three is incorporate the relevant IDE I/O into my monitor PROM and update my CP/M CBIOS so that it can boot directly from an IDE HD or SD card.

Back on topic - I'm certainly willing to assist where I can. I haven't got a PCW yet, but am on the look out for one (I purchased a number of 8256's new back in the day and would like to tinker with one again).

JonB
January 26th, 2017, 11:12 AM
That looks right tasty.

It's very easy to access the IDE drive, using LBA. If you've written a CBIOS this will be trivial for you. Thanks for the offer but I don't need assistance with the PCW. The diver is already working. I meant that I would need your help to get the uIDE running on your M-Three.