Re: VIC-2000 Expander. Modern Power Using Retro Parts!
Posted: Fri Nov 03, 2017 8:53 am
Although I enjoy programming 6502 assembly more than anything, I must admit that the power of HDL is intoxicating!
The display shown in the above photos is basically generated by one line of code that unrolls the character ROM into a stream of pixels.
This entire block of test code executes in one 40MHz cycle...
Imagine how many cycles this would take even on a powerful micro like an ARM!
... makes me feel guilty!
Brad
The display shown in the above photos is basically generated by one line of code that unrolls the character ROM into a stream of pixels.
This entire block of test code executes in one 40MHz cycle...
Code: Select all
if (CHARS[CHARMEM[((HCOUNT-136)/32)+(((VCOUNT-24)/24)*22)]][(((HCOUNT-136)/4)&7)+(((VCOUNT-24)/3)*8)]==1) begin
VGARED <= VICPAL[COLRMEM[((HCOUNT-136)/32)+(((VCOUNT-24)/24)*22)]][3:0];
VGAGRN <= VICPAL[COLRMEM[((HCOUNT-136)/32)+(((VCOUNT-24)/24)*22)]][7:4];
VGABLU <= VICPAL[COLRMEM[((HCOUNT-136)/32)+(((VCOUNT-24)/24)*22)]][11:8];
end else begin
VGARED <= 15;
VGAGRN <= 15;
VGABLU <= 15;
end
... makes me feel guilty!
Brad