Datasheet

Section 10 Serial Communication Interface
Rev. 6.00 Aug 04, 2006 page 345 of 680
REJ09B0145-0600
4. Transmitting
The procedure for transmitting data is as follows.
(1) Set SOL to 1 in SCSR1.
(2) Set both SO1 and SCK1 to 1 in PMR2 to designate the SO
1
and SCK
1
pin functions. Set POF1
to 1 in PMR2 to designate the SO
1
pin as an NMOS open-drain output.
(3) Clear SNC1 in SCR1 to 0, and clear or set SNC0 to 0 or 1, to select 8-bit mode or 16-bit mode.
Set MRKON to 1 in SCR1 to select SSB mode.
(4) Write the transfer data to SDRL/SDRU. Set the tail mark with LTCH in SCR1.
8-bit transfer mode: SDRL
16-bit transfer mode: Upper byte to SDRU, lower byte to SDRL
(5) When STF is set to 1 in SCSR1, SCI1 starts operating and transmit data is output from the SO
1
pin.
(6) After 8-bit or 16-bit data has been transmitted, STF is reset to 0 in SCSR1 and at the same time
IRRS1 is set to 1 in IRR2. Following data transmission, the selected tail mark is output. MTRF
is set to 1 in SCSR1 during tail mark output.
Data can be transmitted continuously by repeating steps (4) to (6). Ensure that SCI1 is in the idle
state before modifying the MRKON bit in SCR1.