The propeller is a great chip, it is simple once you get used to it and works very well for simple applications, but its video output could be better:
- Only 4 colors per area (exactly like NES graphics), only 6 bit color selections
- VGA resolution capped at NTSC resolution because of memory limitations
- Hard to get parallel interface
The solution? An FPGA.
This isn't the first time I have tried to make graphics devices using FPGAs and a parallel interface. Earlier on my #Z80 overpowered compute (possibly before I discovered HaD) I was trying to make... well a Z80 computer, but I overlooked some things and learned some hard lessons. So I had to literally start over. Well anyways I made a semi-nice graphics card designed to interface with the Z80 that also has a VGA connector and 8-bit DAC. It features a Mercury Board that stacks into a makeshift DIP64 socket.
Here is this old board:
I will improve it next time, promise!
And some weird test program I was trying to write for it I found:
Here is the bit configuration of the DAC:
0 red 0
1 red 1
2 grn 0
3 grn 1
4 blu 0
5 blu 1
6 brightness 0
7 brightness 1
This will be a better design than before.
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