; -----------------------------------------------------------------------------
;  Misc MPU I/O.....
;
;       -IRQ  (pin 19) - pulled up thru a 1.5k to +5v only - Not Used
;       -XIRQ (pin 18) - pulled up thru a 1.5k to +5v only - Not Used
;       RESET (pin 17) - comes from the input voltage regulator.
;       PA7/pai/OC1 - (pin 27) - goes to the IAC driver.
;       PA4/OC4/oc1 - (pin 30) - goes to the SA (Ign Amplifer)
;       PA2/IC1     - (pin 32) - conditioned input from the distributor trigger.;       PD1/TxD     - (pin 21) - thru a hi-current driver to Pin-27 (ECU TX)
;       PA6/OC2/oc1 - (pin 28) - to the MUX (INJ-D driver)
;       PD0/RxD     - (pin 20) - from the MUX (Pin-8 ECU RX) ?????
;
;
;  OC1 - IAC driver (pin 27)
;        Output from OC1 directed to PA7 (pin 27)                       $100C
;        Output a 1 (High) to PA7 (pin 27) after successful compare     $100D
;
;  OC3 - Used for progaming the EEPROM.
;
;  OC4 - Ignition Amplifier drive
;
;  IC1 - Distributor trigger input
;
; -----------------------------------------------------------------------------