All Questions
8 questions
4
votes
0
answers
598
views
Was the Game Boy CPU a completely new layout?
As explained on the Wikipedia Game Boy article and Is the Game Boy Sharp LR35902 object-compatible with the 8080/Z-80?, the Game Boy used a custom CPU that was fairly close to being a superset of the ...
- 63.8k
1
vote
1
answer
308
views
Game assembled using RGBDS can't access cartridge RAM
Any writes I do to cartridge RAM on my test game assembled with RGBDS are silently ignored. I wanted to move the stack pointer to cartridge RAM to have more room in high ram to use as a scratchpad, ...
- 1,668
1
vote
1
answer
419
views
Can the window only be moved once per frame on the Game Boy?
I wanted to cover the top part of the screen to use as a status bar for a game. My idea was to use the Game Boy's window feature to do so. But I ran into a problem: The window's size is fixed to be ...
- 1,668
1
vote
0
answers
131
views
Getting a loading seam to work with 2x2 metatiles
I'm working on a prototype for a scrolling loading seam similar to Pokemon where the screen scrolls incrementally by 8 pixels with each direction button press, and new tile graphics are drawn off the ...
- 1,668
4
votes
0
answers
390
views
Game Boy interrupt handler crashes unless I jump to it indirectly
I have an interrupt handler I created, which is meant to reduce the overhead of interrupts as much as possible. Setting up the interrupt handler is done while interrupts are disabled, of course. It ...
- 1,668
5
votes
1
answer
404
views
Can I use cartridge RAM for the stack pointer?
My understanding is that the extra cartridge RAM banks at &A000-&BFFF are battery-backed SRAM that is preserved after powering off the game. If I'm making a simple game that doesn't have a ...
- 1,668
17
votes
2
answers
7k
views
Is the Game Boy Sharp LR35902 object-compatible with the 8080/Z-80?
(Note: by "object-compatible" I mean that the opcodes and their following operands are the same—the assembler produces the same output for equivalant assembler mnemonics. This of course ...
- 27.9k
10
votes
3
answers
4k
views
How does Game Boy / Sharp LR35902 HRAM work?
The Nintendo Game Boy has RAM called "HRAM" (meaning "high ram")
decoded at locations $ff80 through $fffe. (All other decoded
locations in the $ffxx page appear to be I/O device and system
control ...
- 27.9k