Part Number: TMS570LS3137 Tool/software: Hello, We are currently developing a project utilizing the TMS570LS3137 microcontroller. For this purpose, we are employing the TMS570LS3137 Hercules Development Kit (HDK). During the development process, we have encountered certain issues, which we would like to bring to your attention. We would greatly appreciate your assistance in resolving them. Our project makes use of the CAN communication protocol. One of the modules in the system is an HMI device, which is required to communicate with the MCU via CAN. This communication is being monitored through a PCAN interface. Both nodes transmit CAN messages at 100-millisecond intervals. Each message includes a sequence number, which allows us to detect any missed transmissions. The CAN ID assigned to the HMI is numerically lower than that of the MCU. Consequently, when both devices attempt to transmit simultaneously, the HMI wins arbitration and is granted access to the CAN bus, as expected. Although the "Automatic Retransmission of not successful messages" feature is enabled via the DAR bit in the DCAN CTL register, we observed a missing message, as indicated in FIGURE[00] obtained via PCAN-VIEW. The third byte from the right in the data field represents the sequence number. While 9A was expected to follow 99, the sequence jumps directly to 9B, indicating a lost message. In the logs obtained from the HMI (FIGURE[01]), the field labeled “msg#:” indicates the total number of messages, while “skipped msg#:” indicates the number of missed messages. Prolonged testing has shown that the number of missed messages increases over time. Disabling the Automatic Retransmission feature from the CTL register did not result in any significant change in the number of errors, as illustrated in FIGURE[02]. We would like to ask the following questions in this context: How can the Automatic Retransmission feature be correctly configured and operated? In the case of arbitration loss, how can the peripheral ensure that the pending data is retransmitted in the correct order once the bus becomes available? Are there any alternative peripheral-level mechanisms or configurations available to address this issue aside from Automatic Retransmission? The aforementioned figures are provided below for your reference. Kind regards, FIGURE[00] FIGURE[01] FIGURE[02]
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