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Difference of overload and errors using the CAN controller?

How does the CAN controller differentiate the overload frame and the error frame when it was received on the CAN bus?

As far as I know, the theses of two frames have the same frame format. In my project, I mostly came across an error frame, not an overload frame.

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Found the following:

"The congestion frame is identical to the frame of the active error. The only difference is that Frame Overload does not increase the error counters (see the error limit) and does not cause the frame to be retransmitted. Each node can transmit only 2 congestion frames in sequence."

here: http://www.softing.com/home/en/industrial-automation/products/can-bus/more-can-bus/error-handling/overload-frame.php?navanchor=3010518

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You are right: overload frames and error frames look the same. However, the CAN node can distinguish them by the time the frame is received: the congestion frame will occur only during interframe space and the error frame only during the real CAN frame. Source

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Both the Error Frame and the Overload Frame have the same format if the node is an Active node error . But how the CAN controller differentiates both is based on the appearance position in the CAN frame. An error block will be transmitted whenever a node detects an error, while an Overload Frame is only transmitted in IFS (Inter Frame Space).

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