So, in keeping with our promise here’s a short piece on Gameboy Processors, by Anthony Hom
DMG CPU Revisions
“Over the course of the life of the DMG-01 Gameboy, there were a number of CPU revisions. Some people say you get the best sound out of a DMG-01, which I will get to in a later article, but not every DMG-01 came packing the same firepower.
If you are purchasing a pre-modded DMG-01 or a DMG-01 for modding and the ultimate goal for it is to produce music on it, you will want to skip the first few versions of the DMG-01.
In order to identify if your DMG-01 is a suitable version for producing music with, you have to pop off the battery cover and look inside your Gameboy. The battery cover has a clasping tab that clips into the DMG-01 chassis. If you shine a light inside that hole, you will be able to see what version DMG-01 you have.
You should see a printed portion of the circuit board which will read “CPU-0X.” X denoting a number value.
DMG-01 CPU revisions you should try and avoid: CPU-01, CPU-02 and CPU-03.
DMG-01 CPU revisions that are suitable for making music on: CPU-04 through CPU-08.
The problems you will run into with LSDj when using earlier versions of the DMG-01 CPU models are most noticeable in the WAV channel. Playback in the WAV channel will be inaccurate, inconsistent and generally frustrating.
I theorize that WAV playback will also be inaccurate in Nanoloop, however, I do not have a Nanoloop 1.X cart to test this.