CHAPTER 7 DMAC
Preliminary User’s Manual A14874EJ3V0UM
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7.10 DMA Transfer Start Factors
DMA transfer can be started by the following two factors.
(1) Request by external pin (DMARQn)
If the ENn bit of the DCHCn register is set to 1 and the TCn bit is set to 0, the DMARQn signal becomes active in
TI state (n = 3 to 0). If the DMARQn signal becomes active in TI state, the DMAC moves to T0 state and DMA
transfer begins.
(2) Request by software
If the STGn, ENn, and TCn bits of the DCHCn register are set as follows, DMA transfer begins (n = 0 to 3).
•
STGn bit = 1
•
ENn bit = 1
•
TCn bit = 0