HD6475348R Datasheet, PDF (250/487 Pages) Hitachi Semiconductor – Single-Chip Microcomputer

12.1.4 Register Configuration
The PWM timer module has three registers for each channel as listed in table12-2.
Table 12-2 PWM Timer Registers
Initial
Channel Name
Abbreviation R/W
Value Address
1
Timer control register TCR
R/W
H'38
H'FEC0
Duty register
DTR
R/W
H'FF H'FEC1
Timer counter
TCNT
R/(W)* H'00
H'FEC2
2
Timer control register TCR
R/W
H'38
H'FEC4
Duty register
DTR
R/W
H'FF H'FEC5
Timer counter
TCNT
R/(W)* H'00
H'FEC6
3
Timer control register TCR
R/W
H'38
H'FEC8
Duty register
DTR
R/W
H'FF H'FEC9
Timer counter
TCNT
R/(W)* H'00
H'FECA
* The timer counters are read/write registers, but the write function is for test purposes only.
Application programs should never write to these registers.
12.2 Register Descriptions
12.2.1 Timer Counter (TCNT)—H'FEC2, H'FEC4, H'FECA
Bit
7
6
5
4
3
2
1
0
Initial value
Read/Write
0
0
0
0
0
0
0
0
R/W R/W R/W R/W R/W R/W R/W R/W
The PWM timer counters (TCNT) are 8-bit up-counters. When the output enable bit (OE) in the
timer control register (TCR) is set to 1, the timer counter starts counting pulses of an internal
clock source selected by clock select bits 2 to 0 (CKS2 to CKS0). After counting from H'00 to
H'F9, the timer counter repeats from H'00.
The PWM timer counters can be read and written, but the write function is for test purposes only.
Application software should never write to a PW timer counter, because this may have
unpredictable effects.
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