ST10R272L - ASYNCHRONOUS/SYNCHRONOUS SERIAL INTERFACE
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The Loop-Back option (selected by bit S0LB) simultaneously receives the data currently
being transmitted. This may be used to test serial communication routines at an early stage
without having to provide an external network. In loop-back mode the alternate input/output
functions of the Port 3 pins are not necessary.
Note
Serial data transmission or reception is only possible when the Baud Rate
Generator Run Bit S0R is set to ‘1’. Otherwise the serial interface is idle.
Do not program the mode control field S0M in register S0CON to one of the
reserved combinations to avoid unpredictable behavior of the serial interface.
S0CON (FFB0h / D8h)
SFR
Reset Value: 0000h
Bit
Function
S0M
ASC0 Mode Control
0 0 0:
8-bit data
synchronous operation
0 0 1:
8-bit data
async. operation
0 1 0:
Reserved
Do not use this combination!
0 1 1:
7-bit data + parity
async. operation
1 0 0:
9-bit data
async. operation
1 0 1:
8-bit data + wake up bit
async. operation
1 1 0:
Reserved.
Do not use this combination!
1 1 1:
8-bit data + parity
async. operation
S0STP
Number of Stop Bits Selection
async. operation
0:
One stop bit
1:
Two stop bits
S0REN
Receiver Enable Bit
0:
Receiver disabled
1:
Receiver enabled
(Reset by hardware after reception of byte in synchronous mode)
S0PEN
Parity Check Enable Bitasync. operation
0:
Ignore parity
1:
Check parity
S0FE
5
4
3
2
1
0
11
10
9
8
7
6
15
14
13
12
rw
rw
rw
rw
-
rw
rw
rw
rw
rw
rw
rw
-
S0LB
S0R
S0PE
S0
STP
S0
REN
S0
PEN
S0
FEN
S0
OEN
rw
rw
S0OE
S0
ODD
S0
BRS
S0M