Objects at the top of the screen are drawn after the mid-screen interrupt. Objects at the bottom of the screen are drawn after the end-screen interrupt. Thus the code and hardware work on different halves of the screen.
I'm wondering what the mechanism is here to avoid bus contention between the video circuit and the CPU both accessing the VRAM at the same time.
Might be evident from studying the schematic I would suppose...
I'm wondering what the mechanism is here to avoid bus contention between the video circuit and the CPU both accessing the VRAM at the same time.
Might be evident from studying the schematic I would suppose...