chjmartin2 Posted October 31, 2023 Share Posted October 31, 2023 Hi, I am going to be taking on the challenge of writing some demo type projects for the Bally Astrocade. I am very impressed by the capabilities of this very old machine. I can't believe it was released at the same time as the Atari 2600 and was so versatile. I have gotten lots of help setting up my development environment. I am excited to say that I have a modified cart that run 2764 eproms. The good news there is that I can use a W27C512 64K EEPROM by replicating the 8k data 8 times. This means I can compile and run on hardware in a few seconds. My development rig is about 2 feet from my Bally, so rapid testing is possible. I don't know if what I will attempt will not be able to be run by an emulator but of course I'll start there. I'm not sure what projects I want to pursue but task one will be to make a general purpose bitmap converter. Bally Smurf Demo using Modified EPROM Cart with EEPROM Below are some images that I think we can create on the Bally. The palette isn't selected yet but I am sure there are close enough colors among the 256 we have. The program uses K-Means Color Quantization to find 4 good colors for the image. My first goal is to use the Smurf Demo program as a basis but make a general converter for public use. We'll see how far I get. Thanks, Chris 1 Quote Link to comment Share on other sites More sharing options...
128Kgames Posted October 31, 2023 Share Posted October 31, 2023 (edited) Chris you should check out some the graphic sutff Michael Garber was working on with the 512k cart back in the day, I uploaded 2 videos I made of the graphic demos he created, you can view them at the bottom of my page: https://msdconsulting.wixsite.com/128kgames The one with Pikachu was pretty cool... Edited October 31, 2023 by 128Kgames Quote Link to comment Share on other sites More sharing options...
chjmartin2 Posted October 31, 2023 Author Share Posted October 31, 2023 15 minutes ago, 128Kgames said: Chris you should check out some the graphic sutff Michael Garber was working on with the 512k cart back in the day, I uploaded 2 videos I made of the graphic demos he created, you can view them at the bottom of my page: https://msdconsulting.wixsite.com/128kgames The on with Pikachu was pretty cool... I saw them! Believe me, the premise of a 512k bank switching cart is enticing for sure. The backbit pro could probably be modified/utilized to get to 1 meg (or more) with bank switching. For the 512K cart did it bank switch the entirely of the 8K of ram or was it switching 4K at a time. I'd really rather reserve the 4K for execution code and cycle through in 4K chunks using one byte would give you a meg of memory. Two bytes would give you over 200 meg. Anything in between would be clumsy programming but could be done. Curious how the 512K cart worked as I don't yet fully understand the memory map of the Bally or what the Z80 sees. But regardless, I would like to conquer some 8K stuff first. I have another system calling to me at the moment as well, so my plan is to make the bitmap converter, one enhancement and then move on and come back. So many ideas, so little time. Quote Link to comment Share on other sites More sharing options...
128Kgames Posted October 31, 2023 Share Posted October 31, 2023 3 minutes ago, chjmartin2 said: I saw them! Believe me, the premise of a 512k bank switching cart is enticing for sure. The backbit pro could probably be modified/utilized to get to 1 meg (or more) with bank switching. For the 512K cart did it bank switch the entirely of the 8K of ram or was it switching 4K at a time. I'd really rather reserve the 4K for execution code and cycle through in 4K chunks using one byte would give you a meg of memory. Two bytes would give you over 200 meg. Anything in between would be clumsy programming but could be done. Curious how the 512K cart worked as I don't yet fully understand the memory map of the Bally or what the Z80 sees. But regardless, I would like to conquer some 8K stuff first. I have another system calling to me at the moment as well, so my plan is to make the bitmap converter, one enhancement and then move on and come back. So many ideas, so little time. So I was more the "idea man" on the project, wanting a bank switched cart for gaming, so I got the right people together to make it happen and paid for the prototypes to be built. Steve Tucker / Atarimax designed the 4 prototype carts we had made, initially the plan was for "128k" hence I called it the 128k Project. Steve wound up creating 256k carts instead and later upgraded 2 of them to 512k. Steve worked with us and a lot of the people from the Bally / Astrocade scene who post to the ballyalley@groups.io group. Adam archived the material and software which might answer some of the questions you have on his ballyalley website: https://ballyalley.com/documentation/bally128k-com/whatsnew.htm Its a shame we never got to put it into production, I know Michael Garber and I both had games in our head we wanted to release on the Astrocade, and pairing the 512k board along with a 64K RAM expansion would have been amazing... Quote Link to comment Share on other sites More sharing options...
chjmartin2 Posted November 1, 2023 Author Share Posted November 1, 2023 13 hours ago, 128Kgames said: Its a shame we never got to put it into production, I know Michael Garber and I both had games in our head we wanted to release on the Astrocade, and pairing the 512k board along with a 64K RAM expansion would have been amazing... You are still on this side of the ground man. It is never too late ... Quote Link to comment Share on other sites More sharing options...
chjmartin2 Posted November 1, 2023 Author Share Posted November 1, 2023 Hi, The below images are palate matched to the colors available in the Bally 256 color palette. Next step is to encode them to display as a bitmap. I'm nervous that the available pal RGB values are not accurate, but, we will see what happens soon. But without reservation I believe the below images could be displayed on a Bally. Chris Quote Link to comment Share on other sites More sharing options...
chjmartin2 Posted November 2, 2023 Author Share Posted November 2, 2023 First one is what my program thinks it is going to generate. The second one is what MAME says I generated. The third one is what it looks like on real hardware. The colors are not the same as what I have as a system palette. I don't know if it is my TV, if it is the capacitors in the Bally (not likely.) The true to life and my calc picture are much closer than what MAME shows but I have heard that is a known issue in MAME. The work continues. I am just excited that I got a picture on the screen from my converter. Chris Quote Link to comment Share on other sites More sharing options...
chjmartin2 Posted November 3, 2023 Author Share Posted November 3, 2023 Success! The first image is the original input image, the second is the output of the converter, the third is Mame and the fourth is from the Bally. I think my Bally may actually have bad colors. I am going to recap it although I have no idea if any of those impact color. It is POSSIBLE that I may have my hex color codes wrong but I have checked them a bunch of times and I get this from the NTSC test program: I would love it if somebody could run the attached file on real hardware as a comparison. Gargamel.zip 1 Quote Link to comment Share on other sites More sharing options...
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