Search found 21 matches

by PurpleGirl
Yesterday, 11:25
Forum: Hardware and software hacking
Topic: Interrupts:
Replies: 3
Views: 119

Re: Interrupts:

I know you want to do this in software. And this will certainly be interesting. It would be nice to find a way to chain 2 Gigatrons. I'm not sure how one would exactly do that. Sure, one could use dual-ported RAM to get the information out of RAM. Maybe the Out of the first one could be used to send...
by PurpleGirl
17 Nov 2019, 20:09
Forum: Escape Meta Alt Control Shift
Topic: Atari 8-bit architecture and homebrew versions
Replies: 3
Views: 49

Re: Atari 8-bit architecture and homebrew versions

The 2600 demo was impressive. The demos for modified Atari computers and homebrew clones are even more impressive. The Eclaire is another homebrew Atari clone, but it is an FPGA implementation with a turbo Sally and other Atari chips in the FPGA, whereas the 1088 XEL uses authentic Atari chips, with...
by PurpleGirl
16 Nov 2019, 01:10
Forum: Escape Meta Alt Control Shift
Topic: Atari 8-bit architecture and homebrew versions
Replies: 3
Views: 49

Atari 8-bit architecture and homebrew versions

When I was a teen, I owned an Atari 800 that I still have today. Recently, I've been researching the Atari 8-bit computers. It is interesting how the hobbyist and FPGA community have made all sorts of mods and are still using them or homebrew versions of them today. Atari 8-Bit Computer Architecture...
by PurpleGirl
09 Nov 2019, 15:21
Forum: Hardware and software hacking
Topic: Modified Gigatron Design Ideas
Replies: 19
Views: 776

Re: Modified Gigatron Design Ideas

Thank you for your reply and info. The FIFO sounds interesting, though I am unfamiliar with most of the signals other than Dx and Qx. It is interesting that the one you propose has 9 bits. I think they added the last bit for a traffic sync signal, but that could easily be used as a color bit. On the...
by PurpleGirl
02 Nov 2019, 03:29
Forum: Escape Meta Alt Control Shift
Topic: On the shoulders of Giants
Replies: 6
Views: 336

Re: On the shoulders of Giants

Since I see you now have ports planned, I'd like to make a suggestion. I think you should use the 8 bits at the end of the instruction to specify a port address. That way, you could support up to 256 ports. And whoever makes peripherals could use simple address decoder logic to see if it is the devi...
by PurpleGirl
02 Nov 2019, 03:16
Forum: Hardware and software hacking
Topic: Modified Gigatron Design Ideas
Replies: 19
Views: 776

Re: Modified Gigatron Design Ideas

What would be a decent FIFO to use? I never really thought of FIFOs and shift registers. So any information on those would be a good start. Now I am not sure how such a card can tell the Gigatron that it needs data in its FIFO registers or how software could get it. There is currently no way to sign...
by PurpleGirl
31 Oct 2019, 07:33
Forum: Hardware and software hacking
Topic: Modified Gigatron Design Ideas
Replies: 19
Views: 776

Re: Modified Gigatron Design Ideas

A compromise comes to mind. The existing clock (or a clock divider if going for 12.5 Mhz) could be used to drive a pixel counter. The idea of intercepting a NOP instruction to create a video reset could be used on power-up to reset the pixel counter and any other time the pixels being sent might not...
by PurpleGirl
21 Oct 2019, 00:13
Forum: Hardware and software hacking
Topic: Pluggy Reloaded
Replies: 28
Views: 673

Re: Pluggy Reloaded

From what I see, VCC comes from the Gigatron. The USB's VCC comes from the controller chip, and that chip gets it from the Gigatron. I am wondering if the VCC to the chip and the VCC to the USB port are not wired the opposite way on the controller. It seems VCC on the chip should feed the chip and t...
by PurpleGirl
21 Oct 2019, 00:01
Forum: Escape Meta Alt Control Shift
Topic: On the shoulders of Giants
Replies: 6
Views: 336

Re: On the shoulders of Giants

I've been thinking more about a Suite-16 being used as a Gigatron. Obviously, you'd need at least 1 IN port and 2 OUT ports, and ROM. If you had a 16-bit X-Out, I could think of various ways to use those bits. For instance, if you wanted blinkenlights, that leaves 12 bits, and you could have 2 6-bit...
by PurpleGirl
20 Oct 2019, 20:50
Forum: Escape Meta Alt Control Shift
Topic: On the shoulders of Giants
Replies: 6
Views: 336

Re: On the shoulders of Giants

I notice that you sort of planned to address 24-bits of memory by combining the payload with a register, I also read that your jumps and calls are 16-bits. I got to thinking that you could use the payload byte along with the next 2 bytes and do 24-bit jumps and calls. But then I read that you might ...