When you need to drive tens or hundreds of outputs / read tens or hundreds of inputs from a single prototype board, the daisy-chain shift I/O board is your friend.

All pin headers are labeled:

• The output 2x8 headers providing the output and a ground pin for each output for easy wiring
• The input 2x8 headers have a pin for signal and another one for VCC for each input for easy wiring
• The 2x5 header (SV1) is for the input/output registers (data/clock/latch) and VCC/GND for the whole unit
• The 2x3 header (SV2) is for connecting to the next unit, to the right edge of the 2x5 connector

You can use regular flat cables for wiring and for going from unit to next.

Note that any current limits for the chips used apply - don't drive too much current or they're fried.

As a convenience and protection, all outputs require a resistor (e.g. typical 220-470 Ohm per LED) and all inputs require a sink-to-ground resistor (typically 10kOhm).

Four holes in the corners provided for easy installation.