HD6432351 datasheet(153/1025 Pages) RENESAS

153 / 1025 page

Section 5 Interrupt Controller

Rev. 3.00 Sep 15, 2006 page 119 of 988

REJ09B0330-0300

5.6.3

Operation

The interrupt controller has three main functions in DTC and DMAC control.

(1) Selection of Interrupt Source

With the DMAC, the activation source is input directly to each channel. The activation source for

each DMAC channel is selected with bits DTF3 to DTF0 in DMACR. Whether the selected

activation source is to be managed by the DMAC can be selected with the DTA bit of DMABCR.

When the DTA bit is set to 1, the interrupt source constituting that DMAC activation source is not

a DTC activation source or CPU interrupt source.

For interrupt sources other than interrupts managed by the DMAC, it is possible to select DTC

activation request or CPU interrupt request with the DTCE bit of DTCEA to DTCEF in the DTC.

After a DTC data transfer, the DTCE bit can be cleared to 0 and an interrupt request sent to the

CPU in accordance with the specification of the DISEL bit of MRB in the DTC.

When the DTC has performed the specified number of data transfers and the transfer counter value

is zero, the DTCE bit is cleared to 0 and an interrupt request is sent to the CPU after the DTC data

transfer.

(2) Determination of Priority

The DTC activation source is selected in accordance with the default priority order, and is not

affected by mask or priority levels. See section 7.6, Interrupts, and section 8.3.3, DTC Vector

Table, for the respective priorities.

With the DMAC, the activation source is input directly to each channel.

(3) Operation Order

If the same interrupt is selected as a DTC activation source and a CPU interrupt source, the DTC

data transfer is performed first, followed by CPU interrupt exception handling.

If the same interrupt is selected as a DMAC activation source and a DTC activation source or CPU

interrupt source, operations are performed for them independently according to their respective

operating statuses and bus mastership priorities.

HD6432351 Datasheet(PDF) 153 Page - Renesas Technology Corp