Demo Videos:
The final CPC Portable playing "Oh Mummy!":
Build Objectives
In principle, I am not a big fan of case mods. Being a collector of retro computers, I strive to restore and preserve the original hardware. This cost-reduced CPC 464 had an irreparable tape drive that was causing "tape salad". Despite all my efforts I wasn't able to fix the mechanics. I tried finding a replacement datacorder for a justifiable price, but was out of luck - CPCs and spare parts are getting quite pricey on eBay lately. Seems we are running out of CPCs in this world!
Hence, having a CPC with defunct datacorder at hand, I had to take the chance and try to realize an old dream of mine - to create a portable CPC based on the authentic original hardware with unobtrusive modifications that would give me a built-in display (instead of the datacorder), and at least an HxC SDcard disk drive emulator plus some extra memory so that it would become "equivalent" to a CPC 6128. The build process is described here on Hackaday; for now, it's just a photo log, but I'll add descriptions over time and I will also create a more extensive YouTube video at some point.
The required case modifications were quite extensive (the Dremel was my friend on this project!), and, as explained, I am usually not a big fan of destructive and irreversible case mods. However, something has to give in order to make this happen. The mods are all unobtrusive in the sense that the resulting CPC Portable is still clearly recognizable as an Amstrad CPC - the original looks and form factor and color scheme, as well as as much as possible of the original hardware, i.e., the motherboard etc. Modifying the overall form factor is a no-go for me. The hardware and case has to be original. I am also not a big fan of modern "re-engineered" CPC motherboards, emulators, Raspberry Pis, or FPGA solutions in a CPC case.
So my main objectives were:
- original motherboard
- original case and keyboard
- add unobtrusive mods and extensions that would add the desired features
- allow for one external CPC extension card ("MX4 Standard")
- add a decent pair of detachable stereo speakers
A CPC in a laptop case, or a re-engineered modern CPC mainboard with extensions already on board, are both no-gos for me, and albeit interesting approaches, it's not what I want or value and I leave these alleys to other project builders. Projects that, for example, remove the number block & cursor keys from the keyboard, and cut off 35% from the CPC case (including the datacorder) just to reduce its overall length to make it more "portable" are not what I strive for, and again, I leave this kind of "retro computer butchering" to others.
Finally, I didn't want to include the batteries within the case. Batteries might only last so long, then need to be replaced (requires opening the case again), are heavy, and most of the time the CPC Portable will be running from the grid anyway. So I decided to leave the battery external. It's a simple 10000 mAh Powerbank which has enough electric energy to power the Portable for a few hours. As shown in the demo video, it can even supply an extension card (Speak&SID).
Now, it the CPC Portable really portable? Of course it is! My MSI desktop substitute gaming laptop weighs almost a full LBS more; note that the speakers can be removed easily as well, as they are only attached with Velcro. The CPC also still has it internal little mono speaker. Note that the original CPC 464 with datacorder actually still weighs more than the Portable - the tape drive is "heavy metal!"
Build Process
The original Amstrad CPC 464 had a full-size and very spaciously laid out PCB. My original Schneider CPC 464 which I got for my confirmation in April 1985 probably had a MC0001A (or MC0002B) motherboard:
Did Amstrad just waste space? I believe they didn't - before the Ferranti Gate Array became available,...
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very nice project, I had an Amstrad CPC 464 in my childhood and I would have liked amstrad to release a portable Amstrad :-)
Amstrad CPC fan since always, I talk about your project on my Youtube channel hoping to advertise you :-)
https://youtu.be/v5fDSlFJuwM