LAPIS Semiconductor ML610472, User Manual

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ML610471/472/473/Q471/Q472/Q473 User's Manual
Chapter 11 UART
11-3
11.2.2 UART0 Transmit/Receive Buffer (UA0BUF)
Address: 0F290H
Access: R/W
Access size: 8-bit
Initial value: 00H
7 6 5 4 3 2 1 0
UA0BUF U0B7 U0B6 U0B5 U0B4 U0B3 U0B2 U0B1 U0B0
R/W R/W R/W R/W R/W R/W R/W R/W R/W
Initial value 0 0 0 0 0 0 0 0
UA0BUF is a special function register (SFR) to store the transmitted/received data of the UART.
In transmit mode, write transmission data to UA0BUF. To transmit the data consecutively, confirm the U0FUL flag of the
UART0 status register (UA0STAT) becomes "0", then write the next transmitted data to the UA0BUF. Any value written
to UA0BUF can be read.
In receive mode, since data received at termination of reception is stored in UA0BUF, read the contents of UABUF using
the UART0 interrupt at termination of reception. At continuous reception, BA0BUF is updated whenever reception
terminates. Any write to BA0BUF is disabled in receive mode.
The bits, which are not required when any of the 5- to 8-bit data length is selected, become invalid in transmit mode and
are set to “0” in receive mode.
Note:
For operation in transmit mode, be sure to set the transmit mode (UA0MOD0 and UA0MOD1) before setting the
transmitted data in UAOBUF.