Bit 8—Underflow Flag (UNF): Status flag that indicates the occurrence of underflow.
Bit 8: UNF
Description
0
TCNT has not underflowed
[Clearing condition]
(Initial value)
When 0 is written to UNF
TCNT has underflowed
[Setting condition]
1
When TCNT underflows*
Note: * Writing 1 does not change the value.
Bits 7 and 6—Input Capture Control (ICPE1, ICPE0) (Channel 2 Only): These bits, provided
in channel 2 only, specify whether the input capture function is used, and control enabling or
disabling of interrupt generation when the function is used.
When the input capture function is used, a data transfer request is sent to the DMAC in the event
of input capture.
When using the input capture function, the TCLK pin must be designated as an input pin with the
TCOE bit in the TOCR register. The CKEG bits specify whether the rising edge or falling edge of
the TCLK signal is used to set the TCNT2 value in the input capture register (TCPR2).
The TCNT2 value is set in TCPR2 only when the TCR2.ICPF bit is 0. When the TCR2.ICPF bit is
1, TCPR2 is not set in the event of input capture. When input capture occurs, a DMAC transfer
request is generated regardless of the value of the TCR2.ICPF bit. However, a new DMAC
transfer request is not generated until processing of the previous request is finished.
Bit 7: ICPE1
Bit 6: ICPE0
Description
0
0
1
0
Input capture function is not used
Reserved (Do not set)
(Initial value)
1
Input capture function is used, but interrupt due to input capture
(TICPI2) is not enabled
Data transfer request is sent to DMAC in the event of input
capture
1
Input capture function is used, and interrupt due to input
capture (TICPI2) is enabled
Data transfer request is sent to DMAC in the event of input
capture
Rev. 6.0, 07/02, page 301 of 986
RENESAS [ RENESAS TECHNOLOGY CORP ]
