APOLLO Command Module Plan View

A view of the business-end of the ACM board. From top to bottom are:

6 input connectors, 11 output connectors, and 5 configurable input/output connectors (each with associated jumper determining input or output). The I/O connectors are for as-yet unassigned duties.
Output buffers (three large-ish chips) for outputting TTL levels into 50-ohm loads.
Jumpers for setting the mode of the 5 configurable I/O ports.
The 144-pin EPM7512AE 7 ns Altera PLD handling the timing and state functions.
One-shot, buffer combos (one in center, one lower left) to drive the LEDs on the front panel.
The 208-pin EPM7256AE 10 ns Altera PLD defining the available command set, porting data to the CAMAC dataway, and setting operational parameters for the timing PLD.