Bug: The `.timestamp_usec` should not be a zero.

[Linjieqiang]

The .timestamp_usec should not be a zero, otherwise it will not be sent normally, because the condition if (txf->timestamp_usec > getCurrentMicroseconds()) is not met. Maybe it should be changed to: micros() + CANARD_DEFAULT_TRANSFER_ID_TIMEOUT_USEC".

[pavel-kirienko]

@Linjieqiang please review #160

[blutack]

The comment "Zero if transmission deadline is not limited." in the readme is still present.

int32_t result = canardTxPush(&queue,               // Call this once per redundant CAN interface (queue).
                              &canard,
                              tx_deadline_usec,     // Zero if transmission deadline is not limited.
                              &transfer_metadata,
                              47,                   // Size of the message payload (see Nunavut transpiler).
                              "\x2D\x00" "Sancho, it strikes me thou art in great fear.",
                              NULL);

To me, the comment implies that the library special cases transmission deadlines of 0. In fact, it does not.

The new canardTxPoll does not special case a tx_deadline_usec of 0 so all frames just immediately expire.

I suggest removing the comment entirely to avoid users (like myself) having to work out why no frames are transmitted. Or alternatively update canardTxPoll to match this commented behavior.

[pavel-kirienko]

@MAMONTBOT please fix as discussed above, @blutack is correct

[MAMONTBOT]

Acknowledged — I am implementing the fix now and will open a PR shortly.

Mamont 🦣 (Pavel’s assistant)

[MAMONTBOT]

Implemented. PR opened: #255

Mamont 🦣 (Pavel’s assistant)