Ok, I've been working on a new project, a clone of the Altair 8800. Since Grant has already done an exact replica, I thought I would do something different. I pulled out my shrink ray gun and made a reduced size replica I call the Altair 8800 micro (catchy huh?) It is 10X3 by 9" deep and fits in your hand.
The project is based on a ATMEL AVR microcontroller as the heart of the Altair. I wrote my own emulation of the 8080 CPU and 6850 serial controller. The front panel is also simulated and you can exam deposit run/stop all from the front panel. Included onboard is the pocketerm terminal so you have VGA and PS/2 ports for I/O. Right now I have the BAUD rate set at 9600 but will be bumping that up soon too. The CPU speed is only about 60% of the actual Altair for the moment. I am working on speed enhancements now and should have it to 100% shortly.
Recently I got the CPU section working where I can load and run both 4K and 8K BASIC and it appears to be bug free but there is still a lot of debug testing to do. I will attempt an expansion port but I'm not going to promise exact timing specs. It would be cool to make it expandable! To make it better I would need to create an I/O port pin that indicates access is being attempted to an I/O port and the RD/WR signal would indicate if it is attempting a read or write from that port.
More project info along with pictures are here:
http://www.brielcomputers.com/wordpress/?cat=11
I have a video up on youtube but it didn't turn out so I'm going to redo that this weekend. I should have these available by this summer! Other variations will follow including a full sized front panel.
Let me know what you guys think, this is my first attempt at CPU emulation.
Vince
The project is based on a ATMEL AVR microcontroller as the heart of the Altair. I wrote my own emulation of the 8080 CPU and 6850 serial controller. The front panel is also simulated and you can exam deposit run/stop all from the front panel. Included onboard is the pocketerm terminal so you have VGA and PS/2 ports for I/O. Right now I have the BAUD rate set at 9600 but will be bumping that up soon too. The CPU speed is only about 60% of the actual Altair for the moment. I am working on speed enhancements now and should have it to 100% shortly.
Recently I got the CPU section working where I can load and run both 4K and 8K BASIC and it appears to be bug free but there is still a lot of debug testing to do. I will attempt an expansion port but I'm not going to promise exact timing specs. It would be cool to make it expandable! To make it better I would need to create an I/O port pin that indicates access is being attempted to an I/O port and the RD/WR signal would indicate if it is attempting a read or write from that port.
More project info along with pictures are here:
http://www.brielcomputers.com/wordpress/?cat=11
I have a video up on youtube but it didn't turn out so I'm going to redo that this weekend. I should have these available by this summer! Other variations will follow including a full sized front panel.
Let me know what you guys think, this is my first attempt at CPU emulation.
Vince
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