Amstrad CPC 6128

[millim]

Hello Community!

At the time the Amstrad CPC came out in the 80th, I was fascinated what lies within the creativity of computer games. It was my first computer where me and my brothers spent days and nights playing games. What a perfect time looking back from now. It was also the time I got fascinated by how a computer works, I have started to learn digital science and computer programming, finding hacks and game cheats in first place. Well, there is always a way to start with

Now, sever centuries later, I came in touch with the Odroid GO by searching for ESP32 programming and evaluation board references. I liked already the ESP8266 for doing some nice IOT projects on my own for home automation purpose. Then, after purchasing an Odroid GO, I have started to upload some nice EMUs checking some games.

Well, then I was looking for a Amstrad CPC EMU for the Odroid GO. As far as I know, there is no public version available. I was caught by the idea playing my favorite games I was addicted to in my youth 30 years later on this tiny ESP32. How could such a big machine fit to half a square inch of space?

Then I started with the end of mind. Searching for a simulator platform saving me some development time capable to develop the wrapper on a decent PC. On the Amstrad CPC, I searched for a good starting point to develope from. I decided to go for the Caprice Palm OS version. It was the most flexible and most decent version of the original Caprice32 version. Still a mystery to me how to develop an EMU. Well done Ulrich Doewich and Frederic Coste! Every thing else is history.

Here we go, a first pre-release of the ESP32, Odroid GO version of the Caprice CPC engine is made available here:
https://github.com/grantrismo/CapriceESP32

You will find additional notes and a user manual inside the repository.

Have Fun!
millim

[mad_ady]

It's never too later for a new emulator!

[amstradcpc]

Listening to the vocal synthesis of Throne Legacy and Orphée on my Odroid Go, nice !

I will be able to play more to the last games of the CPCRetroDev 2020 in the train going to work now thanks to you.

[millim]

Thank you amstradcpc to make it more popular!

Well, all in all, my gaming skills did not improve since then, so I decided to add a cheat interface to the emulator.
It is based on peeks and pokes. You can find more details inside the repository. In case you need help on the scrips or on the cheat data base, simply PE.

And one thing more, I have added a simple Sound MUTE function to the context menu. So you can play without disturbing others.

So, on the sound, OG is lacking a simple headphone jack. The device is not cheap, I question why a proper external stereo 16-DAC was not added to it? However, I have still some memory left and also 80% power on core 0, I will try to get wireless earbuds working. This will be my next mission.

Keep you posted on updates!
Millim

[amstradcpc]

New version is installed, when flashing it shows v0.7.0, though of course it shows 0.71 in file selection/option menu.

I also use Caprice on a Palm Tungsten, as it's much easier for adventure games. It's also by default a qwerty keyboard.

Would it be possible to be able to add a menu to choose a model/rom language ? 6128 Fr mode, 6128 Uk mode, etc... ? To be able also to use other ROMs like ParaDOS or SymbOS !

But for using SymbOS, RAM expansion would be needed and I dont know if there is enough RAM available ?

[millim]

New version is installed, when flashing it shows v0.7.0, though of course it shows 0.71 in file selection/option menu.

I also use Caprice on a Palm Tungsten, as it's much easier for adventure games. It's also by default a qwerty keyboard.

Would it be possible to be able to add a menu to choose a model/rom language ? 6128 Fr mode, 6128 Uk mode, etc... ? To be able also to use other ROMs like ParaDOS or SymbOS !

But for using SymbOS, RAM expansion would be needed and I dont know if there is enough RAM available ?

Hello amstradcpc,

yes right, it shows still v0.7.0 on the flash. I need to automate version control by scripting.

I also like adventure games and I have also a reference running on my Palm Tungsten T5. Still, on the T5, one can use the pen to navigate the keyboard, this, I think is not possible on the OG. And I am also not confortable with an external keyboard on the OG, what is naturally bulky. On the OG, navigation will be slow, and one may lose fun with the keyboard navigation to get text into it, what is necessary for adventure games. A keyboard is needed to start some games, that's why I have added it. But, this is just my view.

However, I have on my list to make it possible to select the models, roms and keyboard layouts, I just need to enable it and but some glue around it. I keep the same architecture, should be easy.
SymbOS, should be possible, because everything, except some special structures and the display memory, runs from the PSRAM already today. PSRAM can hold up to 4MB.

Still, first I want to close on the overall architecture. As mentioned, I want to get Bluetooth working. At the moment, I was able to fit the BT Classic Stack in parallel to the emu, can connect to a A2DP sink and stream sound across it. It shows acceptable time lag. Working nicely . Now, everything is on the edge on internal memory and processing power. However, the details need to be implemented now:
- Discovering and connecting to BT A2DP devices close by in a comfortable way.
- Seamless switch form internal Speaker to BT.
- Volume control, remote control
- Fine tune sampling rate, and buffer manager, and need to fix some bugs in the esp_idf to get it work.

This will keep me busy the next weeks. After that, I will work in the other features.

millim

[millim]

Dear all,

had a bit of spare time during the Christmas break. I have committed a new release Ver 0.79 to the repository. I have added:
- Key mapping file support, identical to the C64/Schumi structure
- Volume control for the internal speaker. By pressing VOL button together with one key ( left, right, up, or down) will increase/decrease by 1 or 10.
- Bluetooth Audio support. Now you can stream the emulator sound in Stereo to Speaker or Headphone, wirelessly.
- Added a simple 8bit style OSD aka 1986
- Improved SD card access by adding SPI Mutex access control

Again, I recommend reading the user manual part of the repository.

Next, I think it will then Ver. 1.0. (the final release planned), I plan to add:
- snapshot save/restore,
- different CPC module support,
- different ROM support,
- different keyboard layout,
- green monitor emulation, and night color mode.

millim.

[alektronic]

I have committed a new release Ver 0.79 to the repository.

I had a bit of time to try this tonight and it's working really nicely, thanks for your efforts!

[amstradcpc]

Nice, I will try the bluetooth tonight.

Would you be interested in key mapping files for your github ?