SH7011 Datasheet, PDF (134/292 Pages) Renesas Technology Corp – CMOS single-chip microprocessors

Procedure for Setting Buffer Mode (Figure 8.18):
1. Use the timer I/O control register (TIOR) to set the TGR as either an input capture or output
compare register.
2. Use the timer mode register (TMDR) BFA, and BFB bits to set the TGR for buffer mode.
3. Set the CST bit in the TSTR to 1 to start the count operation.
Buffer mode
Select TGR function
(1)
Select buffer mode
(2)
Start counting
(3)
Buffer mode
Figure 8.18 Buffer Operation Setting Procedure
Buffer Operation Examples—when TGR Is an Output Compare Register: Figure 8.19 shows
an example of channel 0 set to PWM mode 1, and the TGRA and TGRC registers set for buffer
operation.
The TCNT counter is cleared by a compare-match B, and the output is a 1 upon compare-match A
and 0 output upon compare-match B. Because buffer mode is selected, a compare-match A
changes the output, and the buffer register TGRC value is simultaneously transferred to the
general register TGRA. This operation is repeated with each occurrence of a compare-match A.
See section 8.4.6, PWM Mode, for details on the PWM mode.
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