devkitPro

Okay, totally scrapping the old post in exchange for a quick and straight question. I found that writing to a single byte wasn't possibly with an 8 bit background. Should reads of one byte work correctly or might you always only get the upper or lower bits?

On the GBA you have to figure out what short the byte is in and read that short , change the byte, then write it back. Since the DS is a superset of the GBA then this would hold for video memory (i assume, not sure)

Hi Gary, thanks for the reply. I'm pretty sure I ended up figuring this one out. What I've got is a 16bit game background and an 8 bit collision bg underneath. The way I got it working was basically like you said, reading in the whole short, checking if my sprites x position was odd or even and then checking the corresponding upper or lower bits. Works very well, actually.

The issue I have now, in another post, is with a scrolling method I worked on and the fact that I'm having trouble using DMA to get the collision bg to scroll the way I want.