Roland SH-101

Information:

Modifications:
The keytranspose function of the SH-101 is not permanent unfortunately. So I decided to add a simple switch parallel to the keytranspose push button. Now I can transpose seque nces or arpeggios without pressing the transpose button. click on this picture to see the places where the switch should be soldered to.
The microprocessor working inside the SH-101 is a Toshiba TMP80C49P-6. The program for this processor is stored in a ROM which is built in to the chip and cannot be rewritten. If this part is broken, you usually have no chance to repair the synth. I tried to read the ROM contents with a BALEP-4 Eprom burner, which can read the contents of some very similar chip. The result is this file:

Roland_Sh101_8049_ROM.bin

With this file it should be possible to program a 87C49 processor, which is the same type but with an EPROM (so it is rewritable). Unfortunately I do not have a 87C49 to test this and also my Galep-4 is not intended to burn these chips. If any of you outside int wide world tested this, please let me know, whether it worked or not.
Update Feb. 2011: The code works fine (confirmed by Senso from www.vintageplanet.nl), but the 87C49 eats too much power from the powersupply of the SH101. So one has to replac e the powersupply too ;-(