Intel 8XC251SP User Manual
8XC251SA, SB, SP, SQ USER’S MANUAL
10-14
Note that timer 2 increments every state time (2T
OSC
) when it is in the baud rate generator mode.
In the baud rate formula that follows, “RCAP2H, RCAP2L” denotes the contents of RCAP2H
and RCAP2L taken as a 16-bit unsigned integer:
and RCAP2L taken as a 16-bit unsigned integer:
NOTE
When timer 2 is configured as a timer and is in baud rate generator mode, do
not read or write the TH2 or TL2 registers. The timer is being incremented
every state time, and the results of a read or write may not be accurate. In
addition, you may read, but not write to, the RCAP2 registers; a write may
overlap a reload and cause write and/or reload errors.
not read or write the TH2 or TL2 registers. The timer is being incremented
every state time, and the results of a read or write may not be accurate. In
addition, you may read, but not write to, the RCAP2 registers; a write may
overlap a reload and cause write and/or reload errors.
Table 10-6 lists commonly used baud rates and shows how they are generated by timer 2.
Table 10-6. Timer 2 Generated Baud Rates
Baud Rate
Oscillator
Frequency
(F
OSC
)
RCAP2H
RCAP2L
375.0 Kbaud
12 MHz
FFH
FFH
9.6 Kbaud
12 MHz
FFH
D9H
4.8 Kbaud
12 MHz
FFH
B2H
2.4 Kbaud
12 MHz
FFH
64H
1.2 Kbaud
12 MHz
FEH
C8H
300.0 baud
12 MHz
FBH
1EH
110.0 baud
12 MHz
F2H
AFH
300.0 baud
6 MHz
FDH
8FH
110.0 baud
6 MHz
F9H
57H
Serial I/O Modes 1 and 3 Baud Rates
F
OSC
32 65536
RCAP2H RCAP2L
)
,
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–
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