read message segment

[clem69]

Hello,

I notice that when I receive an iso tp message with more than 8 bytes of data,
the function UDS_read_2013() first sends a message which allows us to prevent that we are going to receive a segmented message and then we receive the complete message.
can we delete the message that prevents the frame to segment.

thank you

[clem69]

for instance :

normally I have to receive 2 frames but I receive 4

0x88 CA CA CA 00 00 00 00 00
0x88 00 00 00 00 00 00 00 00

0x88 CA CA CA 00 00 00 00 00
0x88 B2 B0 B1 00 00 00 00 00

I want to receive only the last two frames

[K.Wagner]

Hello,

not sure to understand. Please post some code of what you are trying to do in order to better help.

If I understand well, you are sending an UDS request (UDS_Write_2013 ?) and receiving the corresponding confirmation and response. This is the way the protocol works. The confirmation cannot be avoided. If you use the function UDS_WaitForSingleMessage_2013 for dealin with the UDS data, then you can read the confirmation first and discard it, as this function has a parameter (boolean) for this.

Code: Select all

result = UDS_WaitForSingleMessage_2013(PCANTP_HANDLE_USBBUS1, &request, true, 10,
100, &confirmation);

...

result = UDS_WaitForSingleMessage_2013(PCANTP_HANDLE_USBBUS1, &request, false, 10,
100, &response);