Adapted from https://fsf.io/projects/ti994a/spritepainter for use with the HBC-56

Click and drag to paint or erase
If your first click is on an empty cell, you will enter paint mode
If your first click is on a filled cell, you will enter erase mode

The relevant code for ACME assembler will appear below

Top Left: |
Bottom Left: |
Top Right: |
Bottom Right: |
Combined: | Paste ACME !byte statements above to update image from code
Palette: | Paste ACME !byte statements above to update palette from code