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In the AXI4-Stream protocol, the names of the signal that make up a stream are prefixed with T: TDATA, TVALID, TREADY, TLAST, etc.

Does the T prefix have a meaning? "Transfer" comes to mind, but that term is also used in the (non-stream) AXI4 protocol, where the signal names are not prefixed with T.

Martin
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    I would consider these just names, without caring much what the defining guy was drinking or smoking that day. It is a reasonable assumption that it is standing for "transfer" though. – Eugene Sh. Nov 20 '19 at 16:57
  • My guess is the 'S' was already used a lot for AXI slave interfaces (compared to 'M' for master) so they took the next character of 'Stream'. But I have some buddies in Cambridge who regularly see the ARM guys in the pub so maybe after a few drinks they can find out for you, if you pay the beer. – Oldfart Nov 20 '19 at 17:35

1 Answers1

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It would appear to mean 'Transfer'.

The specification does not explicitly state it but it clearly implies it on p1-2, the second page of the spec':

STREAM TERMS

The following stream terms are used in this specification:

TRANSFER  A single transfer of data across an AXI4-Stream interface.
          A single transfer is defined by a single TVALID, TREADY handshake.
          See Handshake process on page 2-3.

The definition of a transfer is that it uses a TVALID/TREADY handshake. So a Transfer is that 'T' being made Valid and accepted by Ready. According to that definition text.

TonyM
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