Analog Devices SHARC ADSP-214 Series Hardware Reference Manual page 231

up DMA transfers, see
page 2-51. The registers that control external port DMA are described
Table 3-24.
Table 3-24. DMA Parameter Registers
Register Description
IIEPx Internal Index
IMEPx Internal Modifier
ICEPx Internal Count
EIEPx External Index
EMEPx External Modifier
ECEPx External Count
CPEPx Chain Pointer
Table 3-25. Enhanced DMA Parameter Registers
Register Description
ELEPx Circular Buffer Length
EBEPx External Base
RIEPx Read Internal Index
RCEPx Read Count
RMEPx Read External Modifier Contains external modifier to be used for delay line reads
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"General Procedure for Configuring DMA" on
Comment
Internal Start Address.
For delay line DMA, it serves as the delay line write
index; for example, the start address of the internal
memory buffer for the external write data.
Internal address modifier.
For delay line DMA, it serves as count for delay line
writes, write block size.
External start address.
External address modifier.
External memory count, read only (alias of ICEPx)
Contains address of the next descriptor in internal
memory.
Comment
Hold circular buffer length for circular, delay line DMA,
scatter/gather DMA.
Hold circular start address for circular, delay line DMA,
scatter/gather DMA.
Contains start address of internal memory buffer to
which the data read from external memory during delay
line DMA reads are to be written into (alias of IIEPx
during delay line DMA).
Contains number of reads from each taplist, read block
size (alias of ICEPx during delay line DMA).
(alias of EMEPx during delay line DMA).
External Port
3-101