G222 Memory Selector

Summary The G222 module is a component used in the PDP-15 computer system for memory addressing. Each module contains four memory selectors, and eight modules are required for every 4K memory stack. The module functions by using a 3-input NAND gate and a bidirectional current switch network to decode X and Y-axis address signals, allowing for the selection of specific paths in an 8 x 8 matrix. The document also provides technical specifications, noting that the NAND gate input presents 2.5 TTL unit loads and the matrix selector switch is capable of handling 400 mA.