User Port to Eprommer Connections:

USER PORT                EPROMMER

1   GND (0v)             GND (0v)
2   +5V                  +5V
3   RESET (active LOW)   n/c
4   CNT1                 n/c
5   SP1                  pins 2 and 12 on both 74LS393's (CLEAR)
6   CNT2                 pin 1 on first 74LS393
7   SP2                  n/c
8   PC2 (active LOW)     n/c
9   ser ATN in           n/c
10  9v AC 100mA          voltage tripler
11  9v AC 100mA          voltage tripler
12  GND (0v)             GND

A   GND (0v)             GND
B   FLAG2 (acive LOW)    n/c
C   PB0                  D0  Data Line to EPROM socket
D   PB1                  D1  
E   PB2                  D2
F   PB3                  D3
H   PB4                  D4
J   PB5                  D5
K   PB6                  D6
L   PB7                  D7
M   PA2                  74LS123 PIN 2 (program pulse gen.)
N   GND (0v)             GND






