SLAU847F October 2022 – March 2026 MSPM0L1105 , MSPM0L1106 , MSPM0L1116 , MSPM0L1117 , MSPM0L1227 , MSPM0L1227-Q1 , MSPM0L1228 , MSPM0L1228-Q1 , MSPM0L1303 , MSPM0L1304 , MSPM0L1304-Q1 , MSPM0L1305 , MSPM0L1305-Q1 , MSPM0L1306 , MSPM0L1306-Q1 , MSPM0L1343 , MSPM0L1344 , MSPM0L1345 , MSPM0L1346 , MSPM0L2116 , MSPM0L2117 , MSPM0L2227 , MSPM0L2227-Q1 , MSPM0L2228 , MSPM0L2228-Q1
This section applies to UNICOMM-UART configurations which support the UART-LIN feature.
The Local Interconnect Network (LIN) protocol standard is based on the UART serial data link format. The LIN communication protocol is a single-commander/multiple-responder topology with message identification for multicast transmission between network nodes.
Figure 25-6 LIN Protocol Message StructureThe LIN commander issues a BREAK field, SYNC field, and PID (Protected Identifier) field at the start of every frame. The four LIN registers are used so that the LIN responder software driver can reasonably detect BREAK and SYNC fields and measure the necessary timing parameters to adjust the baud rate or detect an error.
See the LIN Standards and Specifications page for more information about the LIN protocol standards. The UNICOMM-UART module in LIN mode can operate as a LIN commander or a LIN responder when configured properly. To support the LIN protocol while reducing the number of interrupts needed in software, the following hardware enhancements are included in the UNICOMM-UART module:
Additionally, software can manually control the logic level output of the UNICOMM-UART TXD pin by writing the CTL0.TXD_OUT bit when the CTL0.TXD_OUT_EN is set to 1 with CTL0.TXE set to 0 (transmits disabled). This feature is also needed to achieve a LIN protocol on UNICOMM-UART.