188
Bits 2 to 0: Clock select (TMC2 to TMC0)
Bits 2 to 0 select the clock input to TCC. For external event counting, either the rising or falling
edge can be selected.
Bit 2
TMC2
Bit 1
TMC1
Bit 0
TMC0
Description
0
0
0
Internal clock: ø/8192
(initial value)
0
0
1
Internal clock: ø/2048
0
1
0
Internal clock: ø/512
0
1
1
Internal clock: ø/64
1
0
0
Internal clock: ø/16
1
0
1
Internal clock: ø/4
1
1
0
Internal clock: øw/4
1
1
1
External event (TMIC): rising or falling edge
*
Note:
*
The edge of the external event signal is selected by bit IEG1 in the IRQ edge select register
(IEGR). See 1. IRQ edge select register (IEGR) in 3.3.2 for details. IRQ2 must be set to 1
in port mode register 1 (PMR1) before setting 111 in bits TMC2 to TMC0.
2. Timer counter C (TCC)
Bit
Initial value
Read/Write
7
TCC7
0
R
6
TCC6
0
R
5
TCC5
0
R
4
TCC4
0
R
3
TCC3
0
R
0
TCC0
0
R
2
TCC2
0
R
1
TCC1
0
R
TCC is an 8-bit read-only up-counter, which is incremented by internal clock or external event
input. The clock source for input to this counter is selected by bits TMC2 to TMC0 in timer mode
register C (TMC). TCC values can be read by the CPU at any time.
When TCC overflows from H'FF to H'00 or to the value set in TLC, or underflows from H'00 to
H'FF or to the value set in TLC, the IRRTC bit in IRR2 is set to 1.
TCC is allocated to the same address as TLC.
Upon reset, TCC is initialized to H'00.