CHAPTER 9 TIMER/COUNTER FUNCTION
377
User’s Manual U15195EJ5V0UD
7
OST
TMC31
6
ENT1
5
ALV
4
ETI
3
CCLR
2
ECLR
1
CMS1
0
CMS0
Address
FFFFF688H
After reset
20H
Bit position
Bit name
Function
7
OST
Sets the operation when TM3 overflows.
0: Count operation continues after overflow (free-running mode)
1: After overflow, timer holds 0000H and stops count operation (overflow stop
mode). At this time, the TM3CE bit of TMC30 remains 1. The count operation
is resumed by again writing 1 to the TM3CE bit.
6
ENT1
Enables/disables output of external pulse output (TO3).
0: Disable external pulse output. Output of inactive level of ALV bit to TO3 pin is
fixed. TO3 pin level remains unchanged even if match signal from
corresponding compare register is generated.
1: Enable external pulse output. Compare register match causes TO3 output to
change. However, in capture mode, TO3 output does not change. An ALV bit
inactive level is output from when timer output is enabled until a match signal is
generated.
Caution
If either CC30 or CC31 is specified as a capture register, the ENT1
bit must be set to 0.
5
ALV
Specifies active level of external pulse output (TO3).
0: Active level is low level.
1: Active level is high level.
Caution
The initial value of the ALV bit is “1”.
4
ETI
Switches count clock between external clock and internal clock.
0: Specifies input clock (internal). The count clock can be selected with bits CS2
to CS0 of TMC30.
1: Specifies external clock (TI3). Valid edge can be selected with bits TES31,
TES30 of SESC.
3
CCLR
Enables/disables TM3 clearing during compare operation.
0: Clearing disabled.
1: Clearing enabled (TM3 is cleared when CC30 and TM3 match during compare
operation).
2
ECLR
Enables TM3 clearing by external clear input (TCLR3).
0: Clearing by TCLR3 disabled.
1: Clearing by TCLR3 enabled (counting resumes after clearing).
1
CMS1
Selects operation mode of capture/compare register (CC31).
0: Register operates as capture register.
1: Register operates as compare register.
0
CMS0
Selects operation mode of capture/compare register (CC30).
0: Register operates as capture register.
1: Register operates as compare register.