h8s-2646 Renesas Electronics Corporation., h8s-2646 Datasheet - Page 338

• Manufacturer Part Number: h8s-2646
• Description: Renesas 16-bit Single-chip Microcomputer H8s Family/h8s/2600 Series
• Manufacturer: Renesas Electronics Corporation.

Section 10 16-Bit Timer Pulse Unit (TPU)
Bits 4 and 3—Clock Edge 1 and 0 (CKEG1, CKEG0): These bits select the input clock edge.
When the input clock is counted using both edges, the input clock period is halved (e.g. φ/4 both
edges = φ/2 rising edge). If phase counting mode is used on channels 1, 2, 4, and 5, this setting is
ignored and the phase counting mode setting has priority.
Note: Internal clock edge selection is valid when the input clock is φ/4 or slower. This setting is
Bits 2 to 0—Time Prescaler 2 to 0 (TPSC2 to TPSC0): These bits select the TCNT counter
clock. The clock source can be selected independently for each channel. Table 10.4 shows the
clock sources that can be set for each channel.
Table 10.4 TPU Clock Sources
Channel
0
1
2
3
4
5
Legend:
Blank: No setting
Rev. 5.00 Sep 22, 2005 page 312 of 1136
REJ09B0257-0500
Bit 4
CKEG1
0
1
: Setting
ignored if the input clock is φ/1, or when overflow/underflow of another channel is selected.
φ φ φ φ
/1
Bit 3
CKEG0
0
1
—
φ φ φ φ
/4
φ φ φ φ
/16
Internal Clock
Description
Count at rising edge
Count at falling edge
Count at both edges
φ φ φ φ
/64
φ φ φ φ
/256
φ φ φ φ
/1024
φ φ φ φ
/4096
TCLKA TCLKB TCLKC TCLKD
External Clock
(Initial value)
Overflow/
Underflow
on Another
Channel