HD64F7045F28V Datasheet, PDF (158/925 Pages) Renesas Technology Corp – Renesas 32-Bit RISC Microcomputer SuperH RISC engine Family/SH7040 Series

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
register settings.
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.
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