The TN2224B circuit pack provides 24 DCP ports that can connect to 2-wire terminals such as the 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

• 24-port, 2-wire digital interface.
• Supports 24 digital telephones.
• Supports 6400, 8400, 9400 digital series telephones and 8400B data modules.
• Supports attendant consoles: 302B, 302C, and 302D.
• Terminals must be located within 3500 feet of the main equipment location using 24 gauge cable.
• The TN2224B is an upgraded TN2224 with enhanced firmware, a 24-mHz microcontroller, and 48K of external RAM.