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CP3BT26
9.6.1
Device A Address Counter Register (ADCAn)
The Device A Address Counter register is a 32-bit, read/
write register. It holds the current 24-bit address of either the
source data item or the destination location, depending on
the state of the DIR bit in the CNTLn register. The ADA bit
of DMACNTLn register controls whether to adjust the point-
er in the ADCAn register by the step size specified in the
INCA field of DMACNTLn register. The upper 8 bits of the
ADCAn register are reserved and always clear.
9.6.2
Device A Address Register (ADRAn)
The Device A Address register is a 32-bit, read/write regis-
ter. It holds the 24-bit starting address of either the next
source data block, or the next destination data area, according
to the DIR bit in the DMACNTLn register. The upper 8 bits of
the ADRAn register are reserved and always clear.
9.6.3
Device B Address Counter Register (ADCBn)
The Device B Address Counter register is a 32-bit, read/
write register. It holds the current 24-bit address of either the
source data item, or the destination location, according to
the DIR bit in the CNTLn register. The ADCBn register is up-
dated after each transfer cycle by INCB field of the
DMACNTLn register according to ADB bit of the
DMACNTLn register. In direct (flyby) mode, this register is
not used.
The upper 8 bits of the ADCBn register are re-
served and always clear.
9.6.4
Device B Address Register (ADRBn)
The Device B Address register is a 32-bit, read/write regis-
ter. It holds the 24-bit starting address of either the next
source data block or the next destination data area, accord-
ing to the DIR bit in the CNTLn register. In direct (flyby
)
mode, this register is not used.
The upper 8 bits of the AD-
CRBn register are reserved and always clear.
9.6.5
Block Length Counter Register (BLTCn)
The Block Length Counter register is a 16-bit, read/write
register. It holds the current number of DMA transfers to be
executed in the current block. BLTCn is decremented by one
after each transfer cycle. A DMA transfer may consist of 1 or
2 bytes, as selected by the DMACNTLn.TCS bit.
Note:
0000h is interpreted as 2
16
-1 transfer cycles.
ADCA2
FF F840h
Device A Address
Counter Register
ADRA2
FF F844h
Device A Address
Register
ADCB2
FF F848h
Device B Address
Counter Register
ADRB2
FF F84Ch
Device B Address
Register
BLTC2
FF F850h
Block Length
Counter Register
BLTR2
FF F854h
Block Length Register
DMACNTL2
FF F85Ch
DMA Control Register
DMASTAT2
FF F85Eh
DMA Status Register
ADCA3
FF F860h
Device A Address
Counter Register
ADRA3
FF F864h
Device A Address
Register
ADCB3
FF F868h
Device B Address
Counter Register
ADRB3
FF F86Ch
Device B Address
Register
BLTC3
FF F870h
Block Length
Counter Register
BLTR3
FF F874h
Block Length Register
DMACNTL3
FF F87Ch
DMA Control Register
DMASTAT3
FF F87Eh
DMA Status Register
31
24
23
0
Reserved
Device A Address Counter
Table 18
DMA Controller Registers
Name
Address
Description
31
24
23
0
Reserved
Device A Address
31
24
23
0
Reserved
Device B Address Counter
31
24
23
0
Reserved
Device B Address
15
0
Block Length Counter