SAE J2819:2019 pdf free
SAE J2819:2019 pdf free.TP2.0 Vehicle Diagnostic Protocol
The responding ECU must be able to accept the RX-ID-A sent by the requester as the CAN ID the responder will use to send messages to the requester (TX-ID-P). The responding ECU returns the RX-ID-A as the TX-ID-P in the response or it must reject the channel request. The responder must fill in the RX-ID-P High and Low in the Channel Ack message. The RX-ID-P is the CAN ID that the passive ECU will use to receive messages. The responding passive ECU must be able to accept the application-type and return it in the response or reject the channel request.
After receiving a Channel Ack-Positive Reply, the sending and responding ECU use the Transport Protocol Data Unit Telegrams to send data and manage the channel.
The TPC1 byte defines 7 different TPDU telegram types:.
● Data: The Data telegram is used to send 7 or less bytes of data. A bit in the Data TPC1 tells the receiver if an Ack is expected after the Data telegram.
● Acknowledge: The Ack telegram is used to acknowledge the receipt of the Data telegrams. The SN field in the Ack message is used to request retransmission of data telegram. Normally, SN is equal to the last Data Telegram’s SN + 1. If the Ack’s SN is not equal to the Data telegram’s SN+1, the sender should re-send the data telegrams starting at the telegram who’s SN was specified in the Ack.
● Connection Set-up: The Connection Set-up telegram is used to start a transfer of data. The sending ECU who sends the Connection Set-up is considered the active ECU and is in control of the channel. The sending ECU sends it’s T1 and T3 values to the receiving ECU. The receiving ECU must always space all it’s messages back to the sending ECU by T3.
● Connection Acknowledge: The Connection Acknowledge telegram is sent in response to a Connection Set-up telegram or a Connection Test telegram. The receiving ECU sends it’s T1 and T3 values in this message. The Sending ECU must space it’s messages sent to the receiving ECU by T3.SAE J2819 pdf free download.
