JP8-31.txt

These three JP-8 EPROMs can be used in any JP-8 to give the movable split
point - hold the split button down and press a key.

These are copies of the EPROMs read without their address lines swapped.  
So they can be used to make chips directly.

For disassembling the code, be sure to read the EPROMs with the address lines
 2 and 3 (pins 6 and 5) swapped, to match the PCB.

This is a partial summary of the software options in page 33 of the service manual.

This version works with 12 and 14 bit DACs.  It was used in serial numbers
171700 and 181899.  The later versions were:

3.2  (See below.)

3.4D This (or 3.3D) IS a fouth EPROM.  It is in addition to the three 3.2 
     EPROMs.  It supports the DCB interface and the OC8 board, whatever that
     is.

I don't have these - I just have the three 3.1 chips.

These are raw binary files, to be programmed into a 2716.  

From my notes:

Test switch 1 displays the version number when the power is turned on, and
disabled the auto tune.

If I remember correctly, test switch 2 turns on the LEDs which enable you to 
see which voice is playing.

The arrangement is as follows.


Top left        Top right                 LEDs
Voice Board     Voice Board               1 2 3 4
  B     A         B     A                 5 6 7 8

  4     3         2     1 


Lower left      Lower right
Voice Board     Voice Board
  B     A         B     A

  8     7         6     5 


- Robin Whittle     27 May 2001

   http://www.firstpr.com.au

