I checked the CPU emulation problem and fixed this.
There is a famous program to test 8080 CPU and passed all the tests.
Well, after this.
I am thinking about what to do.
Intel 8080 … Gameboy’s CPU is a subset of 8080 + z80.
Do not you think that it is interesting that similar CPUs can be moved with similar handhelds?
I feel like I can do anything using SD card and 64 Kbyte of memory.
But for that, I need to do something about the BIOS.
Well…
Wow, could you actually emulate the GameBoy’s CPU? Is that really possible due to the slowness of the SPI RAM? As far as I know, 8MHz is the fastest you can go and you have to do a 24-bit transfer just to read or write a single byte.
GameBoy’s CPU is different from z80 or 8080. This is a custom CPU. But it is very similar to 8080.
My program is 8080 emulation, not work GameBoy 's ROM.
SPI RAM is definitely not fast, but it’s late and not problematic.
(It is not suitable for action games etc. However it is a fact that there is no other method.Still it may be operating faster than the actual 8080 machine)
By the way, you can read and write one byte at a time.
Currently my 8080 emulator has passed the famous CPU check program. However, Altair BASIC is not working properly.
The destination seems to be still far.