CC1312R: Contiki-NG: PT_WAIT_UNTIL() does not return

Koichiro Tashiro

Part Number: CC1312R

Hi,

I got a question from my customer about PT_WAIT_UNTIL() usage.

They wants to send data to specified node, then wait until ACK returns.
PT_WAIT_UNTIL() function is used like below codes, but the function does not return.

        /*** Radio tx/rx ***/
        radio_mode = 0;                 // Unicast Mode  
        radio_flag = 1;                 // Send(TX)
        radio_rx_flag = 0;              // Receive(RX)
        process_poll(&udp_unicast_process);
        etimer_set(&et, (5 * CLOCK_SECOND));
//        process_post(&udp_unicast_process, PROCESS_EVENT_SEND, s_tTxRadioData);
        PT_WAIT_UNTIL(pt, 1 == radio_rx_flag || etimer_expired(&et));

Customer thought either raio_rx_flag or etimer condition is met, the PT_WAIT_UNTIL() returns.
They confirmed both conditions are met.
Is there any reason or condition PT_WAIT_UNTIL() does not return?

Please let me know if you need more information from customer.

Thanks and regards,
KoT

over 5 years ago

0 Severin Suveren over 5 years ago

TI__Mastermind 23730 points

Hi KoT,

When you say ACK, do you mean IEEE 802.15.4 ACK or some proprietary application layer ACK?

Either way, are you basing the code snippet on some existing code? I'm not sure what the context here is.

And why are you using PT_WAIT_UNTIL() instead of PROCESS_WAIT_UNTIL()?

0 Koichiro Tashiro over 5 years ago in reply to Severin Suveren

TI__Mastermind 21140 points

Hi Severin,

Thanks for your quick reply.

Please see below flow chart.
Customer is doing communication between two nodes with unicast.
If one node receives data, the node sends the same data back to the sender node.
When they say “Ack”, this means response from their proprietary application layer.

Customer is making the code based on below shell source.
:\contiki-ng\os\services\shell\shell-commands.c

And the reason why they do not use PROCESS_WAIT_UNTIL() is that they want to wait the end of sub-process, not entire process.

Thanks and regards,
KoT

0 Severin Suveren over 5 years ago in reply to Koichiro Tashiro

TI__Mastermind 23730 points

I suppose you are doing UDP communication?

0 Severin Suveren over 5 years ago in reply to Severin Suveren

TI__Mastermind 23730 points

Any updates on this?

0 Koichiro Tashiro over 5 years ago in reply to Severin Suveren

TI__Mastermind 21140 points

Hi Severin,

Sorry for the delay.
Yes, UDP is used for these communication.

Thanks and regards,
KoT

0 Severin Suveren over 5 years ago in reply to Koichiro Tashiro

TI__Mastermind 23730 points

Hi KoT,

It sounds to me that in the sub-process you can busy-wait on either an application event to be posted or an rtimer timeout. The specific event can triggered by the UDP socket connection callback you know the ACK packet will be sent to.

0 Koichiro Tashiro over 5 years ago in reply to Severin Suveren

TI__Mastermind 21140 points

Hi Severin,

Customer confirmed the UDP ACK packet you mentioned in the previous answer works for their objective.
So this thread is closed. Thanks for your support on this!

Thanks and regards,
KoT

Sub-1 GHz

Sub-1 GHz forum

CC1312R: Contiki-NG: PT_WAIT_UNTIL() does not return