At times, too many I/O pins is never enough and sacrifies need to be made. [K]im came up with a setup to expand the number of I/O pins on his MSP430. He uses two serial to parallel converters(74HCT595) to give him an extra 16 pins of output and two parallel to serial converters(74HCT597) for 16 pins of input. His code implements a simple bit-bang procedure to clock in/out code and data. Bit-banging these chips frees up any hardware serial ports that could be useful elsewhere. Detailed schematics and code can be obtained from his site. Backup is linked below in case the site goes down.
Schematic and Code: ZIP

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