HT6542B

The HT6542B is a keyboard controller developed by Holtek with a 4-bit microprocessor. It is pin-to-pin compatible with Intel 8042 keyboard controller used in IBM PC's. PC manufacturers need not modify any printed wiring layout when using it in lieu of the Intel 8042 based keyboard controller. Furthermore, the HT6542B can support a system clock speed of up to 12MHz. It can detect the motherboard type automatically, therefore it can be employed on both of AT and PS/2 motherboard.