HD64F7045F28V Datasheet, PDF (376/925 Pages) Renesas Technology Corp – Renesas 32-Bit RISC Microcomputer SuperH RISC engine Family/SH7040 Series

12.4.5 Cascade Connection Mode
Cascade connection mode is a function that connects the 16-bit counters of two channels together
to act as a 32-bit counter.
This function operates by using the TPSC2–TPSC0 bits of the TCR register to set the channel 1
counter clock to count by TCNT2 counter overflow/underflow.
Note: When channel 1 is set to phase counting mode, the counter clock settings become
ineffective.
Table 12.6 shows the cascade connection combinations.
Table 12.6 Cascade Connection Combinations
Combination
Channel 1, channel 2
Upper 16 Bits
TCNT1
Lower 16 Bits
TCNT2
Procedure for Setting Cascade Connection Mode (Figure 12.22):
1. Set the TPSC2–TPSC 0 bits of the channel 1 timer control register (TCR) to B'111 to select
“count by TCNT2 overflow/underflow.”
2. Set the CST bits corresponding to the upper and lower 16 bits in the TSTR to 1 to start the
count operation.
Cascade connection operation
Select cascade connection ¹
Start counting
2
Cascade connection operation
Figure 12.22 Procedure for Selecting Cascade Connection Mode
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