R8C/1A Group, R8C/1B Group
14. Timers
Rev.1.30
Dec 08, 2006
Page 108 of 315
REJ09B0252-0130
14. Timers
The MCU has two 8-bit timers with 8-bit prescalers, and a 16-bit timer. The two 8-bit timers with 8-bit prescalers are
timer X and timer Z. These timers contain a reload register to store the default value of the counter. The 16-bit timer is
timer C, and has input capture and output compare functions. All the timers operate independently. The count source
for each timer is the operating clock that regulates the timing of timer operations such as counting and reloading.
Table 14.1 lists Functional Comparison of Timers.
Table 14.1
Functional Comparison of Timers
Item
Timer X
Timer Z
Timer C
Configuration
8-bit timer with 8-bit
prescaler (with
reload register)
8-bit timer with 8-bit
prescaler (with
reload register)
16-bit free-run timer
(with input capture
and output compare)
Count
Decrement
Decrement
Increment
Count sources
• f1
• f2
• f8
• fRING
• f1
• f2
• f8
• Timer X underflow
• f1
• f8
• f32
• fRING-fast
Function
Timer mode
Provided
Provided
Not provided
Pulse output mode
Provided
Not provided
Not provided
Event counter mode
Provided
Not provided
Not provided
Pulse width measurement
mode
Provided
Not provided
Not provided
Pulse period measurement
mode
Provided
Not provided
Not provided
Programmable waveform
generation mode
Not provided
Provided
Not provided
Programmable one-shot
generation mode
Not provided
Provided
Not provided
Programmable wait one-
shot generation mode
Not provided
Provided
Not provided
Input capture mode
Not provided
Not provided
Provided
Output compare mode
Not provided
Not provided
Provided
Input pin
CNTR0
INT0
TCIN
Output pin
CNTR0
CNTR0
TZOUT
CMP0_0 to CMP0_2
CMP1_0 to CMP1_2
Related interrupt
Timer X interrupt
INT1 interrupt
Timer Z interrupt
INT0 interrupt
Timer C interrupt
INT3 interrupt
Compare 0 interrupt
Compare 1 interrupt
Timer stop
Provided
Provided
Provided