APPENDIX FOURTEEN



14-pin extension

Top side

Pin     Place   Description
Res     A       Reserved
IRQ     B       Interrupt request line
HALT    C       ANTIC halt signal
A13-15  D-F     Upper three address lines
GND     H       Ground

Bottom side

Pin     Place   Description
EXSEL   1       External device select?
RST     2       System RESET
D1xx    3       Chip select at area $Dlxx
MPD     4       Math pack (FP) disable
AUDIO           5 External audio input
REF     6       Present cycle is a refresh cycle line
+5v     7       Second dc power supply

Looking at the extension from the back, we see:

   A   B   C   D   E   F   H
+-----------------------------+
|  .   .   .   .   .   .   .  |
|                             |
|                             |
|  .   .   .   .   .   .   .  |
+-----------------------------+
   1   2   3   4   5   6   7

A. Reserved     1. EXSEL
B. IRQ          2. RST
C. HALT         3. D1XX
D. A13          4. MPD
E. A14          5. Audio
F. A15          6. REF
H. GND          7. +5v

Atari 65XE
There is no parallel bus on the 65XE; it was dropped by Atari since
third-party manufacturers had not taken advantage of it.