diff --git a/demos/lovebyte2023/tinyhgr_8/README b/demos/lovebyte2023/tinyhgr_8/README index bdb7c005..df8c7a63 100644 --- a/demos/lovebyte2023/tinyhgr_8/README +++ b/demos/lovebyte2023/tinyhgr_8/README @@ -60,8 +60,8 @@ values from uninitialized RAM at boot usually aren't useful. You can try drawing directly to screen -memory at addresses $2000 (PAGE1) -or $4000 (PAGE2), but that takes +memory at addresses $2000* (PAGE1) +or $4000 (PAGE2) , but that takes 3 bytes and if you want to draw to all 8K of the screen you need to have a way to increment a 16-bit @@ -80,6 +80,10 @@ change the color. So is all hope lost? +* note a leading $ is how you + traditionally indicate hexadecimal + numbers on 6502 computers + === THE CHRGET TRICK === We can use a trick I found in a @@ -201,10 +205,10 @@ effects. An obvious choice would be the no-operation NOP instruction, which is $EA. Convenient, as $EAEA points nicely into the ROM. It turns -out there are some fun* complications +out there are some fun** complications with doing this. -* As per 4am, no fun is actually +** As per 4am, no fun is actually guaranteed in this process === WHEREIN WE GET A BEEP AND === @@ -226,7 +230,7 @@ The problem here is BKGND0 assumes the value of the first page of graphics you want to fill is in zero-page location HGR_PAGE ($E6). On bootup -this is likely uninitialzed (it +this is likely uninitialized (it often ends up $00 or $FF), so when you call the routine it happily writes your color pattern across the first 8k