First Word Of Data On Consecutive Dma Transmissions Using Mcbsp Is Lost - Texas Instruments TMS320VC5509A Manual

TMS320VC5509A Silicon Errata
Advisory DL_10
Revision(s) Affected:
Details:
Assembler Notification: None
Workaround:

First Word of Data on Consecutive DMA Transmissions Using McBSP is Lost

1.0 and 1.1
When executing multiple DMA transfers consecutively using the same DMA Transmit Channel
and McBSP, an extra DMA TX request generated by the McBSP at the end of the first transfer
will not be serviced by the DMA until the next DMA transfer is initiated by the McBSP. At the
next DMA transfer, this DMA TX request will be serviced as soon as the DMA TX channel is
enabled.
This transmitted data will remain valid on the bus as long as the McBSP is disabled. However,
once the McBSP is enabled, it sends out another DMA TX request, and the DMA transmits the
second word. This results in the loss of the first word of data on consecutive DMA
transmissions.
Only the systems where McBSP is turned off following each block of DMA transfer are
affected. In such case, a dummy DMA transfer with the DMA synchronization event set to no
sync event will flush out the pending TX request from the McBSP before programming the
DMA to send the next block of data to the McBSP.
SPRZ200E
11