M16C29 Datasheet, PDF (459/499 Pages) Renesas Technology Corp – RENESAS MCU M16C FAMILY / M16C/Tiny SERIES

M16C/29 Group
22. Usage Notes
22.7 Timer S
22.7.1 Rewrite the G1IR Register
Bits in the G1IR register are not automatically set to 0 (no interrupt requested) even if a requested inter-
rupt is acknowledged. Set each bit to 0 by program after the interrupt requests are verified.
The IC/OC interrupt is generated when any bit in the G1IR register is set to 1 (interrupt requested) after all
the bits are set to 0. If conditions to generate an interrupt are met when the G1IR register holds the value
other than 0016, the IC/OC interrupt request will not be generated. In order to enable an IC/OC interrupt
request again, clear the G1IR register to 0016. Use the following instructions to set each bit in the G1IR
register to 0.
Subject instructions: AND, BCL
Figure 22.3 shows an example of IC/OC interrupt i flow chart.
Interrupt⁽¹⁾
G1IRi = 1 ?
No
Yes
Set the G1IRi bit to 0
Process channel i waveform generating interrupt
G1IRj = 1 ?
No
Yes
Set the G1IRj bit to 0
Process channel j time measurement interrupt
G1IR = 0 ?
No
Yes
Interrupt completed
NOTE:
1. Example for the interrupt operation when using the channel i waveform generating interrupt and
channel j time measurement interrupt.
Figure 22.3 IC/OC Interrupt i Flow Chart
Rev. 1.12 Mar.30, 2007 ^{page 435} of 458
REJ09B0101-0112