# Libcanard usage questions **URL:** \ **Category:** Libcanard\ **Created:** [April 21, 2020, 10:25am UTC](https://forum.opencyphal.org/t/libcanard-usage-questions/933 "2020-04-21T10:25:55Z")\ **Posts on this page:** 11\ **Page:** 1
**Author:** ![ifasu](https://forum.opencyphal.org/letter_avatar_proxy/v4/letter/i/94ad74/32.png) [@ifasu](https://forum.opencyphal.org/u/ifasu)\ **Post date:** [April 21, 2020, 10:25am UTC](https://forum.opencyphal.org/t/libcanard-usage-questions/933/1 "2020-04-21T10:25:55Z")
hey .how to test with version 1 for mpc microcontrollers? how can we test without using zubax ? ---
**Author:** ![pavel.kirienko](https://forum.opencyphal.org/user_avatar/forum.opencyphal.org/pavel.kirienko/32/9_2.png) [@pavel.kirienko](https://forum.opencyphal.org/u/pavel.kirienko)\ **Post date:** [April 21, 2020, 10:34am UTC](https://forum.opencyphal.org/t/libcanard-usage-questions/933/2 "2020-04-21T10:34:05Z")
Libcanard is platform-agnostic. You just need to implement the low-level CAN IO routines yourself and integrate them with the library as explained in the README. ---
**Author:** ![ifasu](https://forum.opencyphal.org/letter_avatar_proxy/v4/letter/i/94ad74/32.png) [@ifasu](https://forum.opencyphal.org/u/ifasu)\ **Post date:** [April 21, 2020, 12:29pm UTC](https://forum.opencyphal.org/t/libcanard-usage-questions/933/3 "2020-04-21T12:29:01Z")
okay, since i developed version1 canard for mpc micro-controller do i need any zubax babel (as recommended for version 0)for testing purpose or i can test as explained in README. ---
**Author:** ![ifasu](https://forum.opencyphal.org/letter_avatar_proxy/v4/letter/i/94ad74/32.png) [@ifasu](https://forum.opencyphal.org/u/ifasu)\ **Post date:** [April 27, 2020, 10:16am UTC](https://forum.opencyphal.org/t/libcanard-usage-questions/933/4 "2020-04-27T10:16:46Z")
Why memory allocation error comes during frame queue allocation? I am using your `heap.c` to allocate memory as mentioned in `README.md`. ``` CanardInternalTxQueueItem* const out = (CanardInternalTxQueueItem*) ins->memory_allocate(ins, sizeof(CanardInternalTxQueueItem) + payload_size); ``` ---
**Author:** ![pavel.kirienko](https://forum.opencyphal.org/user_avatar/forum.opencyphal.org/pavel.kirienko/32/9_2.png) [@pavel.kirienko](https://forum.opencyphal.org/u/pavel.kirienko)\ **Post date:** [April 27, 2020, 1:57pm UTC](https://forum.opencyphal.org/t/libcanard-usage-questions/933/5 "2020-04-27T13:57:27Z")
A memory allocation error means that you’re out of memory. ---
**Author:** ![ifasu](https://forum.opencyphal.org/letter_avatar_proxy/v4/letter/i/94ad74/32.png) [@ifasu](https://forum.opencyphal.org/u/ifasu)\ **Post date:** [April 30, 2020, 11:40am UTC](https://forum.opencyphal.org/t/libcanard-usage-questions/933/6 "2020-04-30T11:40:39Z")
how come source node id and destination node id is same in my case? ---
**Author:** ![pavel.kirienko](https://forum.opencyphal.org/user_avatar/forum.opencyphal.org/pavel.kirienko/32/9_2.png) [@pavel.kirienko](https://forum.opencyphal.org/u/pavel.kirienko)\ **Post date:** [April 30, 2020, 6:25pm UTC](https://forum.opencyphal.org/t/libcanard-usage-questions/933/7 "2020-04-30T18:25:58Z")
Generally, when dealing with a technical problem like yours, [good questions yield good answers](https://stackoverflow.com/help/how-to-ask). I am unable to help you because you didn’t provide much relevant information. ---
**Author:** ![ifasu](https://forum.opencyphal.org/letter_avatar_proxy/v4/letter/i/94ad74/32.png) [@ifasu](https://forum.opencyphal.org/u/ifasu)\ **Post date:** [May 3, 2020, 5:53am UTC](https://forum.opencyphal.org/t/libcanard-usage-questions/933/8 "2020-05-03T05:53:23Z")
For sending of data, i am assigning values to payload pointer and after TXpush and Tx peek able to send the data using my driver send function.similarly how to receive data using canard? As per README in RXaccept: ```auto const int8_t result = canardRxAccept(&ins, &received_frame, // The CAN frame received from the bus. redundant_interface_index, // If the transport is not redundant, use 0. &transfer); ``` I am converting my driver format to &received\_frame format and passing it,i am getting the value of result as 0 ,and during debugging i found that source and destination node are same.so i am asking a proper method to receive frame sucessfully. I have a mpc driver so how i wll test its working? ---
**Author:** ![pavel.kirienko](https://forum.opencyphal.org/user_avatar/forum.opencyphal.org/pavel.kirienko/32/9_2.png) [@pavel.kirienko](https://forum.opencyphal.org/u/pavel.kirienko)\ **Post date:** [May 3, 2020, 6:14am UTC](https://forum.opencyphal.org/t/libcanard-usage-questions/933/9 "2020-05-03T06:14:35Z")
Either the received frame is converted incorrectly or the sender emits invalid frames. ---
**Author:** ![ifasu](https://forum.opencyphal.org/letter_avatar_proxy/v4/letter/i/94ad74/32.png) [@ifasu](https://forum.opencyphal.org/u/ifasu)\ **Post date:** [May 3, 2020, 6:46am UTC](https://forum.opencyphal.org/t/libcanard-usage-questions/933/10 "2020-05-03T06:46:35Z")
as far i understand the sending(Txpush,pop,peek)and receiving(rx accept)are independent of each other, okay if received frame conversion causes an error than why source node and destination node are same i am new to canard ---
**Author:** ![pavel.kirienko](https://forum.opencyphal.org/user_avatar/forum.opencyphal.org/pavel.kirienko/32/9_2.png) [@pavel.kirienko](https://forum.opencyphal.org/u/pavel.kirienko)\ **Post date:** [May 4, 2020, 6:35am UTC](https://forum.opencyphal.org/t/libcanard-usage-questions/933/11 "2020-05-04T06:35:58Z")
This forum may not be the best place for learning the basics. I’m sorry but we are unable to debug your code for you. Consider asking at stackoverflow or somewhere else.