TSB42AC3 Datasheet, PDF (41/70 Pages) Texas Instruments – General purpose link layer ideal for a wide-range of applications

TSB42AC3 Data Formats
4.2.2.1 Block Write-Request and Read-Request Packets
The format for a block write-request packet is shown in Figure 4−13. The first quadlet read from the GRF is
the packet token described in section 3.3.4. It contains packet-reception status information added by the
TSB42AC3. The first 16 bits of the second quadlet contains the destination node and bus ID. The remaining
16 bits contains the packet control information. The first 16 bits of third quadlet contains the node and bus ID
of the source. The remaining 16 bits of the third quadlet contains and the entire fourth quadlet contain the
48-bit, quadlet aligned destination offset address. The first 16 bits of the fifth quadlet contain the dataLength
field. The remaining 16 bits represent the extended_tCode field. The block data, if any, follows the
extended_tCode. The format for a block read-request packet is shown in Figure 4−14.
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
Reserved
spd
WriteCount
tCode ackSent
destinationID
sourceID
dataLength
tLabel
rt tCode
destinationOffsetHigh
destinationOffsetLow
priority
block data (if any)
extended_tCode
Figure 4−13. Block-Receive Format (Write Request)
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
Reserved
spd
WriteCount
tCode ackSent
destinationID
sourceID
dataLength
tLabel
rt tCode
destinationOffsetHigh
destinationOffsetLow
extended_tCode
priority
Figure 4−14. Block-Receive Format (Read Request)
4.2.2.2 Block Read-Response and Write-Response Packets
The format for a block read-response packet is shown in Figure 4−15. The first quadlet read from the GRF
is the packet token described in section 3.3.4. It contains the packet-reception information added by the
TSB42AC3. The first 16 bits of the second quadlet contains the destination node and bus ID. The remaining
16 bits contain the packet control information. The first 16 bits of the third quadlet contain the node and bus
ID of the source. The third quadlet also contains the response code of this transaction. The fourth quadlet is
reserved. The first 16 bits of fifth quadlet contains the dataLength field. The remaining 16 bits represent the
extended_tCode field. The block data, if any, follows the extend_tCode. The format for a block write-response
packet is shown in Figure 4−16.
SLLS593A—January 2006
TSB42AC3
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