CMSIS-DAP  Version 1.2.0 (Proposal)
Interface Firmware for CoreSight Debug Access Port
 All Functions Groups Pages
DAP_TI_TransferBlock

Transfer the data that are recorded for various Test Input channels. More...

Transfer the data that are recorded for various Test Input channels.

The DAP_TI_TransferBlock Command initiates the data transfer of a single trace data block of the recorded trace data. The command delivers the content of one trace data block in the Trace Data Management system.

DAP_TI_TransferBlock Request:

| BYTE | BYTE *******|
> 0x20 | DataRequest |
|******|*************|

DAP_TI_TransferBlock Response:

| BYTE | BYTE ***| SHORT ****| WORD ********|+++++++++++++|
< 0x20 | Channel | DataParms | TD_TimeStamp | ChannelData |
|******|*********|///////////|//////////////|+++++++++++++|

The ChannelData reply has depending on DataParms bit 14 two different formats. If ChannelDiff in DAP_TI_Capture Request is set for the specific channel, the Debug Unit may decide the data format depending on the trace data values.

Contiguous Value Format transmits sequentially all data values stored in the trace data buffer. When DataParms bit 14 = 0 the ChannelData has the following format:

|************|************|************|......
| TraceValue | TraceValue | TraceValue |
|************|************|************|......

The size of TraceValue depends on the data size for the channel (see DAP_TI_Info Response, Attributes bit 0..2). DAP_TI_TransferBlock Response is repeated until the number of TraceValues specified by DataParms bit 0 .. 12 is transmitted.

Difference Value Format transmits data values only when there is a significant difference. When DataParms bit 14 = 1 the ChannelData has the following format:

|*************| SHORT *****|*************|......
| TraceValue0 | ValueIndex | TraceValueI |
|*************|////////////|/////////////|......

The size of TraceValue0 and TraceValueI depends on the data size for the channel (see DAP_TI_Info Response, Attributes bit 0..2). DAP_TI_TransferBlock Response is repeated until ValueIndex with bit 15 = 1 is transmitted.

Note
When all data values in the trace buffer are identical, ValueIndex is set to number of data values with bit 15 set to 1.