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Bit 7—Data Transfer Size (DTSZ): Selects the size of data to be transferred at one time.
Bit 7
DTSZ
Description
0
Byte-size transfer
1
Word-size transfer
Bit 6—Data Transfer Increment/Decrement (DTID): Selects incrementing or decrementing of
MAR every data transfer in sequential mode or repeat mode.
In idle mode, MAR is neither incremented nor decremented.
Bit 6
DTID
Description
0
MAR is incremented after a data transfer
•
When DTSZ = 0, MAR is incremented by 1 after a transfer
•
When DTSZ = 1, MAR is incremented by 2 after a transfer
1
MAR is decremented after a data transfer
•
When DTSZ = 0, MAR is decremented by 1 after a transfer
•
When DTSZ = 1, MAR is decremented by 2 after a transfer
Bit 5—Repeat Enable (RPE): Used in combination with the DTIE bit in DMABCR to select the
mode (sequential, idle, or repeat) in which transfer is to be performed.
Bit 5
DMABCR
RPE
DTIE
0
0
1
1
0
1
For details of operation in sequential, idle, and repeat mode, see section 8.5.2, Sequential Mode,
section 8.5.3, Idle Mode, and section 8.5.4, Repeat Mode.
Bit 4—Data Transfer Direction (DTDIR): Used in combination with the SAE bit in DMABCR
to specify the data transfer direction (source or destination). The function of this bit is therefore
different in dual address mode and single address mode.
Description
Transfer in sequential mode (no transfer end interrupt)
Transfer in sequential mode (with transfer end interrupt)
Transfer in repeat mode (no transfer end interrupt)
Transfer in idle mode (with transfer end interrupt)
(Initial value)
(Initial value)
(Initial value)
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