Control Registers - NEC UPD703116 User Manual

10.3.3 Control registers

(1) Asynchronous serial interface mode registers 10, 20 (ASIM10, ASIM20)
The ASIMn0 register is an 8-bit register that controls the UART1, UART2 transfer operation (n = 1, 2).
This register can be read/written in 8-bit or 1-bit units.
Cautions 1. If a bit other than the RXEn bit of the ASIMn0 register is changed during UARTn
transmission or reception, the UARTn operation cannot be guaranteed (n = 1, 2).
2. Set a bit other than the RXEn bit of the ASIMn0 register when the UARTn operation is
stopped (when RXEn bit = 0 and transmission is completed). Change the port 3 mode
control register (PMC3) after setting the communication mode for bits other than the
RXEn bit of the ASIMn0 register.
3. In the case of serial clock output in the clocked (synchronous) mode, ensure that nodes
do not output to one another causing conflicts.
CHAPTER 10 SERIAL INTERFACE FUNCTION
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