Serial Communications (16C452)
Transmit and Receive Buffer Registers
The Transmitter Buffer register and Receiver Buffer register are data
registers holding from five to eight bits of data. If less than eight data
bits are transmitted, data is right justified to the LSB. Bit 0 of a data
word is always the first serial data bit received and transmitted.
The 16C452 data registers are double-buffered so that read and write
operations can be performed at the same time the UART is
performing the parallel-to-serial and serial-to-parallel conversion.
Scratchpad Register
The Scratchpad register (SCR) is an 8-bit Read/Write register that has
no effect on either serial channel. It is intended to be used by the
programmer to hold data temporarily.
8-20
