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CHAPTER 15 DMAC
15.2 DMAC Parameter Descriptor Pointer (DPDP)

The DMAC parameter descriptor pointer (DPDP) is an internal register of the DMAC

and is used to store the first address of the DMAC descriptor table in RAM.

DPDP bits 6 to 0 are always 0, and the first address of the descriptor that can be set is

128 bytes.

DMAC Parameter Descriptor Pointer (DPDP)
The structure of the DMAC parameter descriptor pointer (DPDP) is shown below.
This register is not initialized by resetting.
The register can be read and written.
Use a 32-bit transfer instruction to access the register.
Each descriptor that specifies the operation mode of each channel is placed at the address
specified by the DPDP. Table 15.2-1 lists the addr esses at which individual descriptors are
placed.
31 7 6 0
00000200H
0000000
Initial value: 0000000
Initial value: Undefined
Table 15.2-1 Channel Descriptor Addresses
DMA
channel Descriptor address DMA
channel Descriptor address
0 DPDP + 0 (00H) 4 DPDP + 48 (30H)
1 DPDP + 12 (0CH) 5 DPDP + 60 (3CH)
2 DPDP + 24 (18CH) 6 DPDP + 72 (48H)
3 DPDP + 36 (24H) 7 DPDP + 84 (54H)