GE Brivo OEC 715 Service Manual page 90

Brivo OEC 715/785/865/865 Mobile C-Arm X-Ray Product Service Manual
Key allocation and make/break code
The main control IC of the board is HT82K629A, a
keyboard encoder. It can function both in USB and
PS2 interface environment. What we apply in this
design is the USB interface, and it supports the
USB standard request as well as HID class request
version 1.1.
The pin assignment of HT82K629A is shown in
Picture 4, and the pin description is shown in
Table3
Key matrix forms at the crosses between R0~R7 and C0~C19. Membrane keyboard is adopted as the external
interface of the control board.
Pin description of HT82K629A:
2-36