12/24/2019 10:53 AM | |
Joined: 11/26/2019 Last visit: 1/31/2024 Posts: 2 Rating: (0) |
Hi there, I managed to follow this instruction and was finally able to install and deploy Modbus nodes inside IOT2040 without it crashing. Now, I have a very simple setup to use the RS485 (X31 COM) on the IOT2040 to try and read Analog inputs from an analog input module. (http://www.icpdas.com/root/product/solutions/remote_io/rs-485/tm-series/tm-ad5.html) The device has been configured to 9600 baud rate & Slave/Unit ID = 1.The node-red flow is as attached (txt file). I'm not seeing anything at the Modbus Response node. Kindly advise. Thank you very much in advance.
------------------------------------------------------------------------------------------ Attachmentiot2040_modbus_node-red.txt (237 Downloads) |
Last edited by: Jen_Moderator at: 12/25/2019 12:58:24New subject after splitting |
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1/2/2020 2:56 AM | |
Joined: 11/26/2019 Last visit: 1/31/2024 Posts: 2 Rating: (0) |
In addition to the initial post/question. What I have working (Modbus response node able to see analog input values) is by using a CH340 USB to RS485 converter like this one (https://artofcircuits.com/product/ch340-usb-rs485-converter). This working flow in node red can be seen in the attachment with this post. This hardware setup is direct wiring from the analog input module (tm-AD5) to the PC running the node-red flow. The Modbus node is using COM port. Hence, back to the original question/post. I'm unable read the analog input via the IOT2040 using the X31 COM serial port as RS485 after setting (/dev/ttyS3) in the Modbus Read node. Attachmentiot2040_modbus rtu_CH340.zip (213 Downloads) |