HD6417750RF240V Datasheet, PDF (233/606 Pages) Renesas Technology Corp – Renesas 16-Bit Single-Chip Microcomputer H8S Family/H8S/2600 Series

Section 10 16-Bit Timer Pulse Unit (TPU)
10.4 Operation
10.4.1 Basic Functions
Each channel has a TCNT and TGR register. TCNT performs up-counting, and is also capable of
free-running operation, synchronous counting, and external event counting.
Each TGR can be used as an input capture register or output compare register.
Counter Operation: When one of bits CST0 to CST5 is set to 1 in TSTR, the TCNT counter for
the corresponding channel begins counting. TCNT can operate as a free-running counter, periodic
counter, for example.
1. Example of count operation setting procedure
Figure 10.2 shows an example of the count operation setting procedure.
Operation selection
Select counter clock
[1]
Periodic counter
Select counter clearing source [2]
[3]
Select output compare register
Set period
[4]
Start count operation
[5]
<Periodic counter>
Free-running counter
Start count operation
<Free-running counter>
[1] Select the counter
clock with bits
TPSC2 to TPSC0 in
TCR. At the same
time, select the
input clock edge
with bits CKEG1
and CKEG0 in TCR.
[2] For periodic counter
operation, select the
TGR to be used as
the TCNT clearing
source with bits
CCLR2 to CCLR0 in
TCR.
[3] Designate the TGR
selected in [2] as an
output compare
register by means of
TIOR.
[4] Set the periodic
counter cycle in the
TGR selected in [2].
[5] Set the CST bit in
TSTR to 1 to start
the counter
operation.
Figure 10.2 Example of Counter Operation Setting Procedure
Rev. 7.00 Sep. 11, 2009 Page 197 of 566
REJ09B0211-0700