Invalid frames received

[Sebastian]

Hi all,

I have two PCAN-SUB-FD devices connected to each other. I have to develop LUA applications for the devices to be integrated in our workflow.

For development I control the first one with a LUA script and the second one with the PCAN-View. In LUA I load the provided DLL.

The following is already working without any problems:

Code: Select all

LUA script transmits CAN Message over first device => CAN Message is received on second device and displayed in PCAN-View

This already works without missing any data.

Now to the other direction:

Code: Select all

PCAN-View transmits CAN Message over second device => CAN Message is printed out on LUA command Line

Even that works but with one strange behaviour. The workflow here is the following: I send the same message every five seconds (please have a look at the attachment of PCAN-View).

The messages are received but at the beginning always two CAN Messages are added with all data bytes set to ZERO and I don't know what's going wrong here:

Code: Select all

Program starting as '"D:\Entwicklung\ZeroBraneStudio-1.70\bin\lua.exe" -e "io.stdout:setvbuf('no')" "D:\Entwicklung\Lua\scripts\Pcan_ReadMsg.lua"'.
Program 'lua.exe' started in 'D:\Entwicklung\Lua\scripts' (pid: 8236).

-- Starting suite "main", 1 test(s)
  Available Device Nr. 1: 0x51
===============================
Message ID: 0x1
Msg: Received Data: 0x0
Msg: Received Data: 0x0
Msg: Received Data: 0x0
Msg: Received Data: 0x0
Msg: Received Data: 0x0
Msg: Received Data: 0x0
Msg: Received Data: 0x0
Msg: Received Data: 0x0
Timestamp: 0xA324A34A
Message ID: 0x1
Msg: Received Data: 0x0
Msg: Received Data: 0x0
Msg: Received Data: 0x0
Msg: Received Data: 0x0
Msg: Received Data: 0x0
Msg: Received Data: 0x0
Msg: Received Data: 0x0
Msg: Received Data: 0x0
Timestamp: 0xA324A4C3
Message ID: 0x5
Msg: Received Data: 0x57
Msg: Received Data: 0x12
Msg: Received Data: 0x34
Msg: Received Data: 0x15
Msg: Received Data: 0x8A
Msg: Received Data: 0xBC
Msg: Received Data: 0xF8
Msg: Received Data: 0xE4
Timestamp: 0xA324A7C9
Message ID: 0x5
Msg: Received Data: 0x57
Msg: Received Data: 0x12
Msg: Received Data: 0x34
Msg: Received Data: 0x15
Msg: Received Data: 0x8A
Msg: Received Data: 0xBC
Msg: Received Data: 0xF8
Msg: Received Data: 0xE4
Timestamp: 0xA324A9ED
Message ID: 0x5
Msg: Received Data: 0x57
Msg: Received Data: 0x12
Msg: Received Data: 0x34
Msg: Received Data: 0x15
Msg: Received Data: 0x8A
Msg: Received Data: 0xBC
Msg: Received Data: 0xF8
Msg: Received Data: 0xE4
Timestamp: 0xA324AC12
Message ID: 0x5
Msg: Received Data: 0x57
Msg: Received Data: 0x12
Msg: Received Data: 0x34
Msg: Received Data: 0x15
Msg: Received Data: 0x8A
Msg: Received Data: 0xBC
Msg: Received Data: 0xF8
Msg: Received Data: 0xE4
Timestamp: 0xA324AE36
CAN Queue ist empty: Status 0x20
.
---- Testing finished in 469.00 ms, with 2 assertion(s) ----
  1 passed, 0 failed, 0 error(s), 0 skipped.
Program completed in 0.61 seconds (pid: 8236).

If I call the script after 10 seconds I receive 2 valid frames and the two additional "false" frames. If I call the scripts ater 60 seconds, I receive 12 valid frames and again the two additional "false" frames.

I'm very glad for any hints!

Kind regards
Sebastian

[M.Maidhof]

Hi,

please check the MSGTYPE of those additional frames. This could be status or errorframes, because PCAN-View is transmitting to a CAN bus without having a second active node on the bus (no ack). So the CAN-Controller on the PCAN-View side will resend the message with 100% busload, until your app is active again. This could cause errorframes at the initialization process of your app.

regards

Michael

[Sebastian]

Hi Michael,

thanks for the very fast and helpful answer! I did so and only print the frames if it is not an error or status frame. By printing out the message type I get this output, after the error frame there is a MSGTYPE of 0x14.

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-- Starting suite "main", 1 test(s)
  Available Device Nr. 1: 0x51
===============================
Message type: 0x80
Error frame received
Message type: 0x80
Error frame received
Message type: 0x14
Message ID: 0x5
Msg: Received Data: 0x57
Msg: Received Data: 0x12
Msg: Received Data: 0x34
Msg: Received Data: 0x15
Msg: Received Data: 0x8A
Msg: Received Data: 0xBC
Msg: Received Data: 0xF8
Msg: Received Data: 0xE4
Timestamp: 0x66FF7AD
Message type: 0x14
Message ID: 0x5
Msg: Received Data: 0x57
Msg: Received Data: 0x12
Msg: Received Data: 0x34
Msg: Received Data: 0x15
Msg: Received Data: 0x8A
Msg: Received Data: 0xBC
Msg: Received Data: 0xF8
Msg: Received Data: 0xE4
Timestamp: 0x66FF9D2
Message type: 0x14
Message ID: 0x5
Msg: Received Data: 0x57
Msg: Received Data: 0x12
Msg: Received Data: 0x34
Msg: Received Data: 0x15
Msg: Received Data: 0x8A
Msg: Received Data: 0xBC
Msg: Received Data: 0xF8
Msg: Received Data: 0xE4
Timestamp: 0x66FFBF6
CAN Queue ist empty: Status 0x20

In the header file I cannot find value of the MSGTYPE set to 0x14. Is it logical or'd and does mean that it is a PCAN_MESSAGE_ESI as well as a PCAN_MESSAGE_FD message?

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#define PCAN_MESSAGE_ESI             0x10U  // The PCAN message represents a FD error state indicator(CAN FD transmitter was error active)
#define PCAN_MESSAGE_FD              0x04U  // The PCAN message represents a FD frame in terms of CiA Specs

Kind regards
Sebastian

[M.Maidhof]

Hi,

yes, it is a bit combination. Please check your bitrate settings for FD again on both sides. You must use the same settings, otherwise CAN FD will not work correctly.

best regards

Michael