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Preliminary User’s Manual U17566EE1V2UM00
Chapter 8 DMA Controller (DMAC)
The microcontroller includes a direct memory access (DMA) controller (DMAC)
that executes and controls DMA transfers.
Note
Throughout this chapter, the individual channels of the DMA Controller are
identified by “n”.
The DMAC controls data transfer between memory and I/O or among I/Os,
based on DMA requests issued by the on-chip peripheral I/O, or software
triggers.
8.1 Features
• Four independent DMA channels
• Transfer units: 8, 16 and 32 bits
• Maximum transfer count: 65536 (2
16
)
• Two transfer modes independently selectable for each DMA channel
– Single transfer mode
– Block transfer mode
• Transfer requests
– Requests by dedicated peripheral interrupts of
– µPD70(F)3420, µPD70(F)3421, µPD70F3423: CSIB0, CSIB1,
UARTA0, UARTA1, IIC0, IIC1, TMG0, TMP0, TMP1, TMZ0, TMZ1,
TMZ2, ADC
– µPD70F3424, µPD70F3425: CSIB0…CSIB2, UARTA0, UARTA1, IIC0,
IIC1, TMG0, TMP0, TMP1, TMZ0, TMZ1, TMZ2, LCDIF, ADC
– Requests by software trigger
• Transfer objects
• DMA transfer completion flag
• Automatic restart function
• Forcible DMA termination by NMI
Source \
Destination
Internal RAM
Peripherals
Internal RAM
–
√
Peripherals
√
√
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