SLUUDH5 January   2026

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1 Introduction
  5. 2 Overview of the Software Drivers for an EVSE Development Platform
  6. 3 Recommended Test Setup for the AM62L-EVM and the AM62L-EVSE-DEV-EVM
  7. 4 Software Out of Box with the AM62L-EVM and the AM62L-EVSE-DEV-EVM
  8. 5 EVerest: Open Source Electric Vehicle Charging Infrastructure
  9. 6 Testing PLC Communications
  10. 7 Testing CAN Communications
  11. 8 Testing UART Communications AM62L-EVM and the AM62L-EVSE-DEV-EVM
  12. 9 Lab Testing Setup for the MSPM0
  13. 10Summary
  14. 11Additional Information and Resources

8 Testing UART Communications AM62L-EVM and the AM62L-EVSE-DEV-EVM

The best test method for testing the UART communications of the AM62L and AM62L-EVSE-DEV-EVM board combination is to connect two AM62L EVMs with respective AM62L-EVSE-DEV-EVM boards together. This method for a test setup will be easiest way to demonstrate communication with a UART link partner. This section is written to comprehend this type of setup. This is the diagram from the recommended setup section provided as a quick reference showing the two-board setup.

Two-board Setup Figure 8-1 Two-board Setup

For RS485 Testing:

Take 2 AM62L + AM62L-EVSE-DEV-EVM boards (we will call them Board A & Board B). Wire the connections between the 2 boards as per the table below.

Table 8-1 RS485 Testing
Board A Board B
RS485 N ßà RS485 N
RS485 P ßà RS485 P
RS GND ßà RS GND

See the following diagram for more details.

RS485 Testing Figure 8-2 RS485 Testing

For RS232 Testing:

Take 2 AM62L + AM62L-EVSE-DEV-EVM boards (we will call them Board A & Board B). Wire the connections between the 2 boards as per the table below.

Table 8-2 RS232 Testing
Board A Board B
RS232 TX ßà RS232 RX
RS232 RX ßà RS232 Tx
RS GND ßà RS GND

See the following diagram for more details.

RS232 Testing Figure 8-3 RS232 Testing

As pointed out earlier in the document, there is a device tree source overlay (dtso) file has that describes the interfaces on the AM62L-EVSE-DEV-EVM board has been provided as device tree binary (dtbo). This dtbo for the AM62L-EVSE-DEV-EVM board has the necessary UART interface configurations. The code assumes that the dtbo has been added to the uEnv.txt file in U-Boot.

Testing:

For RS485 the UART port on Linux is ttyS4

For RS232 the UART port on Linux is ttyS3

Replace the <name-of-the-port> in the commands given below to appropriate UART port as per your tests.

Use stty command to configure the UART interface on each board

stty -F /dev/<name-of-th-port> 9600 cs8 -cstopb -parenb raw -echo

Use the commands below to test

On Board A:

head -c 34 < /dev/<name-of-th-port>; echo -n "0123456789ABCDEFGHIJKMNOPQRSTUVWXZ" > /dev/<name-of-th-port>

On Board B:

echo -n "0123456789ABCDEFGHIJKMNOPQRSTUVWXZ" > /dev/<name-of-th-port>; head -c 34 < /dev/<name-of-th-port>

You should see the data being sent and read on both the boards. See the image below:

Board A:

Board B:

If the data being sent and received is not the same then the test is failed.