Datasheet

Section 12 8-Bit Timers
Rev. 6.00 Mar. 18, 2010 Page 458 of 982
REJ09B0054-0600
12.7 Interrupt Sources
12.7.1 Interrupt Sources and DTC Activation
The 8-bit timer can generate three types of interrupt: CMIA, CMIB, and OVI. Table 12.2 shows
the interrupt sources and priority. Each interrupt source can be enabled or disabled independently
by interrupt enable bits in TCR. Independent signals are sent to the interrupt controller for each
interrupt. It is also possible to activate the DTC by means of CMIA and CMIB interrupts.
Table 12.2 8-Bit Timer Interrupt Sources
Interrupt source Description Flag DTC Activation
Interrupt
Priority
CMIA0 TCORA_0 compare-match CMFA Possible High
CMIB0 TCORB_0 compare-match CMFB Possible
OVI0 TCNT_0 overflow OVF Not possible Low
CMIA1 TCORA_1 compare-match CMFA Possible High
CMIB1 TCORB_1 compare-match CMFB Possible
OVI1 TCNT_1 overflow OVF Not possible Low
CMIA2
*
TCORA_2 compare-match CMFA Possible High
CMIB2
*
TCORB_2 compare-match CMFB Possible
OVI2
*
TCNT_2 overflow OVF Not possible Low
CMIA3
*
TCORA_3 compare-match CMFA Possible High
CMIB3
*
TCORB_3 compare-match CMFB Possible
OVI3
*
TCNT_3 overflow OVF Not possible Low
Note: * Not available in the H8S/2237 Group and H8S/2227 Group.
12.7.2 A/D Converter Activation
The A/D converter can be activated only by channel 0 compare match A.
If the ADTE bit in TCSR0 is set to 1 when the CMFA flag is set to 1 by the occurrence of channel
0 compare match A, a request to start A/D conversion is sent to the A/D converter. If the 8-bit
timer conversion start trigger has been selected on the A/D converter side at this time, A/D
conversion is started.