h8s-2628 Renesas Electronics Corporation., h8s-2628 Datasheet - Page 245

• Manufacturer Part Number: h8s-2628
• Description: Renesas 16-bit Single-chip Microcomputer H8s Family/h8s/2600 Series
• Manufacturer: Renesas Electronics Corporation.

10.4
10.4.1
Each channel has a TCNT and TGR register. TCNT performs up-counting, and is also capable of
free-running operation, periodic 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 CST5 to CST0 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
Basic Functions
Select output compare register
Select counter clearing source
Figure 10.2 Example of Counter Operation Setting Procedure
Start count operation
Select counter clock
Operation selection
<Periodic counter>
Periodic counter
Set period
[1]
[2]
[3]
[4]
[5]
<Free-running counter>
Free-running counter
Start count operation
Section 10 16-Bit Timer Pulse Unit (TPU)
Rev. 3.00 Oct 04, 2005 page 205 of 598
[1]
[2]
[3]
[4]
[5]
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.
For periodic counter
operation, select the
TGR to be used as
the TCNT clearing
source with bits
CCLR2 to CCLR0 in
TCR.
Designate the TGR
selected in [2] as an
output compare
register by means of
TIOR.
Set the periodic
counter cycle in the
TGR selected in [2].
Set the CST bit in
TSTR to 1 to start
the counter
operation.
REJ09B0155-0300