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CHAPTER 18 SERIAL INTERFACE CHANNEL 1
(2) Automatic transmit/receive data setting
(a) Transmit data setting
<1> Write transmit data from the least significant address FAC0H of buffer RAM (up to FADFH at
maximum). The transmit data should be in the order from high-order address to low-order address.
<2> Set to the automatic data transmit/receive address pointer (ADTP) the value obtained by
subtracting 1 from the number of transmit data bytes.
(b) Automatic transmit/receive mode setting
<1> Set bit 7 (CSIE1) to 1 and bit 5 (ATE) to 1 of the serial operating mode register 1 (CSIM1) to 1.
<2> Set bit 7 (RE) of the automatic data transmit/receive control register (ADTC) to 1.
<3> Set a data transmit/receive interval in the automatic data transmit/receive interval specify register
(ADTI).
<4> Write any value to the serial I/O shift register 1 (SIO1) (transfer start trigger).
Caution Writing any value to SIO1 orders the start of automatic transmit/receive operation and
the written value has no meaning.
The following operations are automatically carried out when (a) and (b) are carried out.
After the buffer RAM data specified with ADTP is transferred to SIO1, transmission is carried out (start
of automatic transmission/reception).
The received data is written to the buffer RAM address specified with ADTP.
ADTP is decremented and the next data transmission/reception is carried out. Data transmission/
reception continues until the ADTP decremental output becomes 00H and address FAC0H data is
output (end of automatic transmission/reception).
When automatic transmission/reception is terminated, bit 3 (TRF) of ADTC is cleared to 0.