Input Capture Mode - Renesas M16C Series Hardware Manual

R8C/11 Group

12.4.1 Input Capture Mode

This mode uses an edge input to TC
generates an interrupt request. The TC
noise or so on from occurring. Table 12.13 shows specifications in input capture mode. Figure 12.33
shows an operation example of input capture mode.
Table 12.13 Input Capture Mode Specifications
Item
Count source
Count operation
Count start condition
Count stop condition
Interrupt request
generation timing
______
INT3/TC pin function
IN
P10 to P12, P33 to P35
pin function
Counter value reset timing
(1)
Read from timer
Write to timer
Select function
NOTES:
1. TC register and TM0 register must be read in 16-bit units.
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2. The INT3 interrupt is acknowledged by digital filter delay and one count source cycle delay (max.)
Rev.1.20 Jan 27, 2006
REJ09B0062-0120
pin or the f
IN
IN
f , f , f , f
1 8 32 RING-fast
• Count up
• Transfer value in TC register to TM0 register at active edge of measurement pulse
• Value in TC register is set to "0000
TCC00 bit in TCC0 register is set to "1" (count start)
TCC00 bit in TCC0 register is set to "0" (count stop)
• When active edge of measurement pulse is input [INT3 interrupt]
• When Timer C overflows [Timer C interrupt]
Programmable I/O port or measurement pulse input (INT3 interrupt input)
Programmable I/O port
When TCC00 bit in TCC0 register is set to "0" (capture disabled)
• Count value can be read out by reading TC register.
• Count value at measurement pulse active edge input can be read out by reading TM0
register.
Write to TC register and TM0 register is disabled
_____
• INT3/TC polarity select function
IN
Measurement pulse active edge is selected by TCC03 to TCC04 bits
• Digital filter function
Digital filter sampling frequency is selected by TCC11 to TCC10 bits
• Trigger select function
TC input or f
IN RING128
page 105 of 204
clock as trigger to latch the timer value and
RING128
input has a digital filter and this prevents an error caused by
Specification
" when a counting stops
16
is selected by TCC07 bit.
12.4 Timer (Timer C)
_____
(2)
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