My original opinion also still stands. This said, you've shown considerable improvement since post one, but so far, the majority of songs that you've created wouldn't really work out as part of an OST.
You need to keep practicing & determine for yourself (from the opinions of others) whether or not each song you make should be incorporated into your OST.
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Technology: the one thing that's hated & cursed at by all engineers, technologists, scientists & technicians!
DMC is the name of the channel, Delta Modulation Channel. It is not a format.
The DMC's output is a 7-bit PCM through a 7-bit DAC. PCM = Pulse Code Modulation, which is a series of numbers representing the signal level. DAC = Digital to Analog Converter, which converts PCM to an analog signal.
The DMC's PCM value can be driven by directly writing that number (raw), or by a 1-bit DPCM sample. DPCM is the format it uses for sample playback.
DPCM means Delta Pulse Code Modulation. Instead of storing a series of 7-bit PCM samples, we store only the difference between successive samples as a 1-bit delta. Every sample, the counter value either goes up by 1 or down by 1. Also, the counter that stores the reconstructed PCM sample is only 6-bit, so actually our output sound for DPCM has 6-bit resolution even though we have a 7-bit DAC.
The resolution of the input format is not the same as the output resolution. The DMC channel always outputs a 7-bit signal, whether it's raw or DPCM. When you're using DPCM, the DPCM decoder turns it into a 6-bit PCM. The signal coming out is NOT 1-bit.
If you need more information you can find it here: http://web.textfiles.com/games/dmc.txt
Another way of putting this is that the DMC is utterly incapable of playing a square wave via DPCM samples. If it were 1-bit output it would be able to play them very well.
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