MS51
Nov. 28, 2019
Page
118
of 491
Rev 1.00
MS51
32K
SE
RIES
TE
CHNICAL RE
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EREN
CE MA
N
UAL
T3CON
– Timer 3 Control
Register
SFR Address
Reset Value
T3CON
C4H, Page 0
0000_0000 b
7
6
5
4
3
2
1
0
SMOD_1
SMOD0_1
BRCK
TF3
TR3
T3PS[2:0]
R/W
R/W
R/W
R/W
R/W
R/W
Bit
Name
Description
7
SMOD_1
Serial port 1 double baud rate enable
Setting this bit doubles the serial port baud rate when UART1 is in Mode 2. See Table 6.9-2
Serial Port UART1 Mode / baudrate Description for details.
6
SMOD0_1
Serial port 1 framing error access enable
0 = SCON_1.7 accesses to SM0_1 bit.
1 = SCON_1.7 accesses to FE_1 bit.
5
BRCK
Serial port 0 baud rate clock source
This bit selects which Timer is used as the baud rate clock source when serial port 0 is in Mode 1
or 3.
0 = Timer 1.
1 = Timer 3.
4
TF3
Timer 3 overflow flag
This bit is set when Timer 3 overflows. It is automatically cleared by hardware when the program
executes the Timer 3 interrupt service routine. This bit can be set or cleared by software.
3
TR3
Timer 3 run control
0 = Timer 3 is halted.
1 = Timer 3 starts running.
Note that the reload registers RH3 and RL3 can only be written when Timer 3 is halted (TR3 bit is
0). If any of RH3 or RL3 is written if TR3 is 1, result is unpredictable.
2:0
T3PS[2:0]
Timer 3 pre-scalar
These bits determine the scale of the clock divider for Timer 3.
000 = 1/1.
001 = 1/2.
010 = 1/4.
011 = 1/8.
100 = 1/16.
101 = 1/32.
110 = 1/64.
111 = 1/128.