[sdiy] E-Drum antics, EPROM data dumping

[Rainer Buchty]

>I just got a "Willem" EPROM reader/burner PCB recently, so I figure I
>should use it to try to rip the data off of the ROMs. By studying the
>ripped data I hope to understand how the audio data is formatted on
>there. But even if I can extract the data off of the ROM... I'd expect
>it'd look like hex or binary gibberish to me. I really wonder how I am
>going to recognize audio data by sifting through the contents! Time to
>get my windoze machine out of the mothballs and onto the bench!

My bet is 8-bit unsigned, i.e. 0x80 is 0, 0x00 is -128 and 0xff is 127.
If they spare a length indicator, then maybe the value 0x00 is used as
wave-end marker. Ensoniq did it that way.

To figure out what that hex gibberish means I recommend a proper hex
editor with ASCII output (like khexedit, but since you're in the Windows
domain, khexedit is not for you :) and a basic sound editor which allows
interpreting data in different formats such as 8 vs 16 bit, signed vs.
unsigned.

Rainer