CT8022 Datasheet, PDF (39/194 Pages) List of Unclassifed Manufacturers – VOIP/VON G.723.1, G279AB TRUESPEECH CO-PROCESSOR

Version: 1.18
PRELIMINARY/CONFIDENTIAL
TrueSpeech® Co-Processor
4.6.3 Flow-Through DMA Transfers
Programmer’s Note:
A Flow-Through DMA transfer is one in which the read and write operations of the DMA transfer
take place as separate cycles, with the DMA controller providing intermediate temporary storage of
the data. In this type of DMA, the data physically flows through the DMA controller:
• DMA controller outputs source address
• DMA controller reads from source
• DMA controller stores data in internal temporary register (single byte)
• DMA controller outputs destination address
• DMA controller writes data to destination
Address
Data
RDN
WRN
RXDREQ
HSTCS/
RXDACK/
CT8022 RX Buffer Addr Destination Memory Addr.
Data From 8022
Data From 8022
Figure 4-6: Flow-Through DMA
Figure 4-6 is an example of a CT8022 to Memory DMA transfer using Flow-Through DMA. The RXDACK/ signal
is not used. Note that, from the perspective of the CT8022, an access by a Flow-Through type DMA controller
looks identical to a normal Host access. The Intel 80186 and 80188 processors contain this type of DMA controller.
CT8022A11AQC FW Revision 0118
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All specifications are subject to change without prior notice.