HD6412240 RENESAS [Renesas Technology Corp], HD6412240 Datasheet - Page 408

• Manufacturer Part Number: HD6412240
• Description: Renesas 16-Bit Single-Chip Microcomputer H8S Family / H8S/2200 Series
• Manufacturer: RENESAS [Renesas Technology Corp]

Section 10 8-Bit Timers
Each pair of registers for channel 0 and channel 1 is a 16-bit register with the upper 8 bits for
channel 0 and the lower 8 bits for channel 1, so they can be accessed together by word transfer
instruction.
10.2
10.2.1
Bit
Initial value
R/W
TCNT0 and TCNT1 are 8-bit readable/writable up-counters that increment on pulses generated
from an internal or external clock source. This clock source is selected by clock select bits CKS2
to CKS0 of TCR. The CPU can read or write to TCNT0 and TCNT1 at all times.
TCNT0 and TCNT1 comprise a single 16-bit register, so they can be accessed together by word
transfer instruction.
TCNT0 and TCNT1 can be cleared by an external reset input or by a compare match signal.
Which signal is to be used for clearing is selected by clock clear bits CCLR1 and CCLR0 of TCR.
When a timer counter overflows from H'FF to H'00, OVF in TCSR is set to 1.
TCNT0 and TCNT1 are each initialized to H'00 by a reset and in hardware standby mode.
Rev.3.00 Mar. 26, 2007 Page 366 of 772
REJ09B0355-0300
Register Descriptions
Timer Counters 0 and 1 (TCNT0, TCNT1)
:
:
:
R/W
15
0
R/W
14
0
R/W
13
0
R/W
12
TCNT0
0
R/W
11
0
R/W
10
0
R/W
9
0
R/W
8
0
R/W
7
0
R/W
6
0
R/W
5
0
R/W
TCNT1
4
0
R/W
3
0
R/W
2
0
R/W
1
0
R/W
0
0