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CHAPTER 14 SERIAL INTERFACE CHANNEL 1
278
User
’
s Manual U11302EJ4V0UM
(2) Automatic transmit/receive data setting
(a) Transmit data setting
[1] Write transmit data from the least significant address of buffer RAM, FAC0H (up to FAFFH).
The transmit data should be in the order from higher address to lower address.
[2] Set the automatic data transmit/receive address pointer (ADTP) to the value obtained by
subtracting 1 from the number of transmit data bytes.
(b) Automatic transmit/receive mode setting
[1] Set bit 7 (CSIE1) and bit 5 (ATE) of serial operating mode register 1 (CSIM1) to 1.
[2] Set RE of the automatic data transmit/receive control register (ADTC) to 1.
[3] Set the data transmit/receive transfer interval in the automatic data transmit/receive interval
specification register (ADTI).
[4] Write any value to serial I/O shift register 1 (SIO1) (transfer start trigger).
Caution Writing any value to SIO1 orders the start of an automatic transmit/receive operation;
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 by 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 by 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 the
data of address FAC0H is output (end of automatic transmission/reception).
When automatic transmission/reception is terminated, bit 3 (TRF) of ADTC is cleared to 0.