SH7041A datasheet(156/923 Pages) RENESAS

156 / 923 page

118

6.6.2

Handling DMAC Activating Sources but Not CPU Interrupt or DTC Activating

Sources

1. Select the DMAC as a source and set the DME bit to 1. CPU interrupt sources and DTC

activating sources are masked regardless of the interrupt priority level register settings or DTC

2. Activating sources are applied to the DMAC when interrupts occur.

3. The DMAC clears activating sources at the time of data transfer.

6.6.3

Handling DTC Activating Sources but Not CPU Interrupt or DMAC Activating

Sources

1. Either do not select the DMAC as a source, or clear the DME bit to 0.

2. For DTC, set the corresponding DTE bits to 1 and clear the DISEL bits to 0.

3. Activating sources are applied to the DTC when interrupts occur.

4. When the DTC performs a data transfer, it clears the activating source. An interrupt request is

not sent to the CPU, because the DTE bit is maintained as a 1.

5. However, when the transfer counter value = 0 the DTE bit is cleared to 0 and an interrupt

request is sent to the CPU.

6. The CPU performs the necessary end processing in the interrupt processing routine.

6.6.4

Treating CPU Interrupt Sources but Not DTC or DMAC Activating Sources

1. Either do not select the DMAC as a source, or clear the DME bit to 0.

2. For DTC, clear the corresponding DTE bits to 0.

3. When interrupts occur, interrupt requests are sent to the CPU.

4. The CPU clears the interrupt source and performs the necessary processing in the interrupt

processing routine.

SH7041A Datasheet(PDF) 156 Page - Renesas Technology Corp