Intel 8XC251SA, Руководство пользователя

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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:
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.
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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