name: HT9320A function: 22-Memory Tone/Pulse Dialer package: DIP28,28 manufacturer: Holtek +--()--+ C8B | 1 28| C7B HST | 2 27| C6B R1B | 3 26| C5B R2B | 4 25| C4B R3B | 5 24| C3B R4B | 6 23| C2B R5B | 7 22| C1B HKSB | 8 21| POB M/BB | 9 20| HFO HFI |10 19| XMUTEB MODE |11 18| DTMF X1 |12 17| HDIB X2 |13 16| HDO VDD |14 15| VSS +------+ This pinout came from the Chipdir: http://www.chipdir.org/