NEC PD78214 - Manual (Page 148)

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Chapter 7 Timer/Counter Units
7
Fig. 7-11 Capture Operation
Remark Dn: TM0 count value (n = 0, 1, 2, ...)
CLR01 = 0
Caution With an in-circuit emulator, digital noise on the INTP3 pin cannot be removed correctly. When the capture function is used, the
operation described below is performed if an edge is detected erroneously.
• When IE-78210-R is used
Capture operation is performed on an erroneously detected edge. At this time, an interrupt request is also generated on the edge.
• When other in-circuit emulators are used
Capture operation is not performed on an erroneously detected edge. However, an interrupt request is generated on the edge.
Accordingly, the capture value must be used after checking by software to see if the INTP3 interrupt was generated normally or
generated on an erroneously detected edge. For detailed information about erroneous edge detection, see Section 11.4.
7.1.6 Basic Operation of Output Control Circuit
The output control circuit controls the levels of the timer outputs (TO0, TO1) according to the overflow signal or
the coincidence signal from the compare registers. The operation of the output control circuit is determined by
the timer output control register (TOC) and capture/compare control register 0 (CRC0). (See Table 7-5.)
Before a timer output (TO0 or TO1) signal can be output on a pin, the pin must be placed in the control mode by
the PMC3 register.
Count starts
CE0 ←1
TM0
count value
D0 D1 D2
D2
D1
FFFFH
0H
INTP3
pin input
INTP3
interrupt request
Capture
register
(CR02)
OVF0
D0