AM2434: AM2434 MCAN issue

lin meng

Part Number: AM2434
Other Parts Discussed in Thread: SYSCONFIG, LP-AM243

We make CANOpen protocol on AM2434 by using MCAN as data Transmit and Receive.

But we got the problem：

when slave got a synchronization object 0x80 and RxPDO1 0x202, RxPDO2 0x302, RxPDO3 0x402 sending from Master，and slave should reply by sending TxPDO1 0x182, TxPDO2 0x282 nad TxPDO3 0x382,

after the system run a while, slave can not sent TxPDO1, TxPDO2,TxPDO3 but got MCAN ErrorCode 7.

the receive and transmit messagebox configuration as follows:

over 2 years ago

+1 Fleenor over 2 years ago

TI__Mastermind 22863 points

[deleted]

0 lin meng over 2 years ago in reply to Fleenor

Prodigy 30 points

Hello,

Attached is a MCAN test project. Can you help debug and locate the problem

s800d-MCAN测试.zip

0 Fleenor over 2 years ago in reply to lin meng

TI__Mastermind 22863 points

Hello,

Glad to hear you are able to implement the CANOpen protocol with the MCAN IP on AM243x, but sorry to hear you are running into this issue. We have some follow up questions included below to help find a resolution.

Can you provide example code and associated SysConfig files so that we can test this on our end as well?
How long does the system execute before the peripheral(slave) fails to respond to the host(master)?
What is meant by MCAN ErrorCode 7?

Thank you for providing these files!

We will take a look at the code provided and see if we can replicate on our side.

0 Dean Zeng over 2 years ago in reply to Fleenor

TI__Intellectual 890 points

Hi Fleenor,

Master can communication with slave, but stop after several hundreds frame data, CAN communication stop with 7 in MCAN_PSR register.

Can you test the provided code? the error should be represented. Thanks!

Best Regards,

Dean

0 Fleenor over 2 years ago in reply to Dean Zeng

TI__Mastermind 22863 points

Hello Dean,

I am working on getting an AM243x EVM so I can test provided code. Does your current implementation use TMDS243GPEVM or LP-AM243?

I am including the PSR register description below for reference.

According to this, a value of 7 indicates that no CAN bus event was detected since the last CPU read to the PSR register.

0 lin meng over 2 years ago in reply to Fleenor

Prodigy 30 points

Hello,

The core problem I need is that after thousands of times of communication with the CANOPEN protocol stack, the program is stuck waiting for the semaphore to be sent. The MCAN ErrorCode you see is 7 or 3.

1.The CANOPEN protocol stack runs normally for a short time. As shown in the figure below:

2.CANOPEN protocol stack runs for a long time, and the program is stuck waiting for sending the completed semaphore. As shown in the figure below:

0 Dean Zeng over 2 years ago in reply to Fleenor

TI__Intellectual 890 points

Hi Fleenor,

We tested the code in TMDS243GPEVM, same error happen.

Best Regards,

Dean

0 Fleenor over 2 years ago in reply to Dean Zeng

TI__Mastermind 22863 points

Hey Dean,

Thanks for checking this on the GPEVM. What is the SW tool being used to capture communications on the CAN bus?

I have acquired an AM243xLP and will attempt to replicate the issue on our side today.

Best Regards,

Zackary Fleenor

+1 Fleenor over 2 years ago in reply to Fleenor

TI__Mastermind 22863 points

Hey Dean,

I am having trouble when attempting to execute your example code.

Can you please try again using the latest MCU+SDK for AM243x (version 08.04..00.17)?

Latest MCU+SDK Link:

MCU-PLUS-SDK-AM243X Software development kit (SDK) | TI.com

0 lin meng over 2 years ago in reply to Fleenor

Prodigy 30 points

Hey Fleenor,

I use MCU+SDK for AM243x (version 08.03. 00.18). You can compile with this version.

0 Fleenor over 2 years ago in reply to lin meng

TI__Mastermind 22863 points

I do not have access to this version of the SDK.

We recommend always using the latest SW/SDK releases. This allows us to better assist in the debug process while providing SW traceability/dependency tracking for future development/release phases.

0 Dean Zeng over 2 years ago in reply to Fleenor

TI__Intellectual 890 points

Hi Fleenor,

We can build and test attached code in our side. Can you try it again? Or we can setup a meeting to discuss it.

Best Regards,

Dean

0 Fleenor over 2 years ago in reply to Dean Zeng

TI__Mastermind 22863 points

Hey Dean,

We still request testing with the latest MCU+SDK for AM243x (version 08.05.00.24). Is this possible?

lock mcu_plus_sdk_am243x_08_05_00_24-windows-x64-installer.exe — 107106 K (ti.com)

If issue is still experienced, we can setup a meeting with the right experts for additional debug.

Best Regards,

Zackary Fleenor

0 lin meng over 2 years ago in reply to Fleenor

Prodigy 30 points

Hi Fleenor,

We used the latest SDK to test on the TMDS243GPEVM board, and the same error occurred.

Attached is a MCAN test project.

Best Regards,

AM2434 MCAN Test.zip

0 Aakash Kedia over 2 years ago in reply to lin meng

TI__Mastermind 26145 points

Hi lin meng,

I checked the attached project.

lin meng said:
AM2434 MCAN Test.zip

These are my observations -

1. In case of receiving CANID 0x80, at an interval of 1ms (Host Machine was sending 1 packet every 1ms) the issue was reproducible.

2. After receiving 1 packet, 32 packets are transmitted by am243x which takes 200us to send 1 packet and 7.7ms to send 32 packets.

Root Cause Analysis -

The Rx-IDs received by am243x are smaller than Tx-ID being sent by am243x. Due to synchronization problems, the msgs are received and transmitted at the same time. According to the CAN protocol, the smaller pktID takes in the precedence on the bus, hence the CAN-Tx stops due to Rx taking the bus precedence. After successful Rx, the Tx cannot resume as the packet was not originally sent and gets stuck on the Semaphore_pend.

Recommended Solutions -

1. Fix the synchronization in the system. Make sure to not send the messages when the data is being received. In case of pkt received, to resend the packet, start from the very first.

2. If this is very difficult to do in the software, then use the Disable Automatic Retransmission in MCAN_CCCR. To do the same in software add the following code in App_mcanConfig.

With this enabled the packet will be re-transmitted again incase of failure to send which suits your use-case but you might see some packet losses during transmission.

Regards,
Aakash