Datasheet

Section 7 Data Transfer Controller [H8S/2138 Group]
Rev. 4.00 Jun 06, 2006 page 172 of 1004
REJ09B0301-0400
On-chip
supporting
module
IRQ interrupt
DTVECR
Selection circuit
Interrupt controller
CPU
DTC
DTCER
Clear
control
Select
Interrupt
request
Source flag cleared
Clear
Clear request
Interrupt mask
Figure 7.3 Block Diagram of DTC Activation Source Control
When an interrupt has been designated a DTC activation source, existing CPU mask level and
interrupt controller priorities have no effect. If there is more than one activation source at the same
time, the DTC is activated in accordance with the default priorities.