TN2224B 2-Wire Digital 24 Port Circuit Pack

The TN2224B provides twenty-four DCP ports that can connect to two-wire terminals such as the 2400, 6400, 8400, or 9400 series digital voice terminals and the 302C attendant console. The TN2224B is the equivalent of a TN2224 with enhanced firmware, a 24-MHz microcontroller, and 48k of addressable external RAM.