uPD780065 Subseries PUM - Renesas Electronics

15.2 Serial Interface (SIO30) Configuration
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CHAPTER 15 SERIAL INTERFACE (SIO30)
The serial interface (SIO30) includes the following hardware.
Table 15-1. Serial Interface (SIO30) Configuration
Item Configuration
Registers Serial I/O shift register 30 (SIO30)
Control registers Serial operation mode register 30 (CSIM30)
(1) Serial I/O shift register 30 (SIO30)
This is an 8-bit register that performs parallel-serial conversion and serial transmit/receive (shift operations)
synchronized with the serial clock.
SIO30 is set by an 8-bit memory manipulation instruction.
When “1” is set to bit 7 (CSIE30) of the serial operation mode register 30 (CSIM30), a serial operation can be
started by writing data to or reading data from SIO30.
When transmitting, data written to SIO30 is output to the serial output (SO30).
When receiving, data is read from the serial input (SI30) and written to SIO30.
RESET input resets SIO30 to 00H.
Caution Do not access SIO30 during a transmit operation unless the access is triggered by a transfer
start. (Read operation is disabled when MODE0 = 0 and write operation is disabled when
MODE0 = 1.)
Preliminary User’s Manual U13420EJ2V0UM00