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A comment on Emulating the Original Gameboy’s CPU.

Re:Emulating the Original Gameboy’s CPU by nottorp on Friday December 27, 2019 @04:37PM (#21894903)
"The Gameboy’s CPU is known as the DMG CPU. It is equipped with 6 registers of 16 bit each and they’re called AF, BC, DE, HL, SP and PC."

Those look like Z80 register names. Guess it's a Z80 and the article autor doesn't know that?

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Re:Emulating the Original Gameboy’s CPU by DanBC on Friday December 27, 2019 @04:41PM (#21894950)
It's not really a Z80. This article talks about the differences: https://realboyemulator.wordpress.com/2013/01/01/the-nintend...

Or this one: https://gbdev.gg8.se/wiki/articles/CPU_Comparision_with_Z80

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Re:Emulating the Original Gameboy’s CPU by userbinator on Friday December 27, 2019 @05:05PM (#21895153)
I suspect Nintendo may have started with a Z80 core and then customised it a little bit, similar to what they did with the almost-6502 in the NES.
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Re:Emulating the Original Gameboy’s CPU by simias on Friday December 27, 2019 @06:13PM (#21895650)
It's definitely based on the Z80, but it's also different enough that you can't really base yourself on Z80 docs to implement the Game Boy CPU (I learned that the hard way). The flags are different, the timings are different, some instructions are removed, some instructions are added etc...
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Re:Emulating the Original Gameboy’s CPU by nottorp on Friday December 27, 2019 @07:14PM (#21896045)
Ahaaa... I live and learn. About long dead CPUs.
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Re:Emulating the Original Gameboy’s CPU by RetroSpark on Friday December 27, 2019 @07:21PM (#21896086)
It's more like a cut-down Z80. Some registers are missing (note the list excludes IX and IY), as are some instructions (but a few others are added) and even some of the status flags.

The official name of the CPU is unknown - there's some discussion of that here: https://forums.nesdev.com/viewtopic.php?f=20&t=18335

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Re:Emulating the Original Gameboy’s CPU by djmips on Friday December 27, 2019 @05:03PM (#21895139)
I guess you didn't know about the 8080 and how the Z80 is it's child?
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