name: HT93214CL function: 1-Memory Tone/Pulse Dialer package: DIP20,20 manufacturer: Holtek +--()--+ LOCK | 1 20| NC HKSB | 2 19| R4B MODE | 3 18| R3B X1 | 4 17| R2B X2 | 5 16| R1B VSS | 6 15| C3B VDD | 7 14| C2B DTMF | 8 13| C1B XMUTEB | 9 12| POB DOUT |10 11| CLOCK +------+ This pinout came from the Chipdir: http://www.chipdir.org/