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CHAPTER 17 SERIAL INTERFACE CHANNEL 1
(2) Setting of automatic transmit/receive data
(a) Setting of transmit data
<1> Write the transmit data from the lowest address FAC0H of the buffer RAM (up to FADFH).
However, the data must be transmitted from the high-order address to the low-order address.
<2> Set the value of the number of transmit data bytes minus 1 to the automatic data transmit/receive
address pointer (ADTP).
(b) Setting of automatic transmit/receive mode
<1> Set CSIE1 and ATE of the serial operation mode register 1 (CSIM1) to 1.
<2> Set RE of the automatic transmit/receive control register (ADTC) to 1.
<3> Set a data transmit/receive interval to the automatic data transmit/receive interval specification
register (ADTI)
<4> Write any value to the serial I/O shift register 1 (SIO1) (transfer start trigger).
Caution
Writing any value to SIO1 is to indicate the start of the automatic transmit/receive
operation, and the written value has no meaning.
The following operation is automatically executed by performing (a) and (b) above.
After the data in the buffer RAM specified by ADTP has been transferred to SIO1, transfer is executed
(start of the automatic transmit/receive operation).
Received data is written to an address of the buffer RAM specified by ADTP.
The contents of ADTP are decremented, and the next data is transmitted/received. Data transmission/
reception is performed until the output of the decrementer of ADTP reaches 00H, and the data at address
FAC0H is output (end of the automatic transmit/receive operation).
When the automatic transmit/receive oeration is completed, TRF is cleared to 0.