Skip to Content

Register Login

Industry Online Support

Technical Forum

Navigation

Modbus RTU 485 problem

Created by: jmonzon at: 9/13/2022 9:51 AM (8 Replies)

Rating (2)

Thanks 4

9 Entries

9/13/2022 9:51 AM	Rate (0)
jmonzon Regular Member Joined: 6/15/2021 Last visit: 6/6/2023 Posts: 48 Rating: (0)	Hi everyone, I've been trying to connect the IoT2050 to a Eurotherm 3216 controller. I`m using node-red (v3.0.2) with node-red-contrib-modbus (v5.23.1). The node.js version is 12.22.5. For some reason I cannot understand I'm not able not communicate properly. I've tested the same configuration with my usual PC and didn't see any problem. I suppose is a pheripheral problem but I don't know how do I have to setup the correct properties. Does anyone know what the problem might be? Thank you so much for your help!

Suggestion To thank Quote Answer

9/13/2022 11:19 AM	Rate (1)
rfond Advanced Member Joined: 6/8/2018 Last visit: 12/17/2024 Posts: 113 Rating: (5)	Hello, Have you configured the serial communication port? In commande line sudo iot2050setup Peripherals Configure External COM Ports For exemple I communicate with regulator in Modbus RS485. So RS485 Turn on terminate resistor 0x0005 0x0005 Reboot

Suggestion To thank Quote Answer
This contribution was helpful to 1 thankful Users jmonzon

9/13/2022 11:21 AM	Rate (1)
rfond Advanced Member Joined: 6/8/2018 Last visit: 12/17/2024 Posts: 113 Rating: (5)	To complet. Verify pin to communicate : https://support.industry.siemens.com/forum/WW/en/posts/rs485-pinout-iot2050/265145

Suggestion To thank Quote Answer
This contribution was helpful to 1 thankful Users jmonzon

9/13/2022 12:52 PM	Rate (0)
jmonzon Regular Member Joined: 6/15/2021 Last visit: 6/6/2023 Posts: 48 Rating: (0)	Hi, I've done as you say, but the problem persists.

Suggestion To thank Quote Answer

9/13/2022 1:13 PM	Rate (0)
rfond Advanced Member Joined: 6/8/2018 Last visit: 12/17/2024 Posts: 113 Rating: (5)	When i do : `dmesg \| grep tty` root@iot2050-debian:/home/siemens# dmesg \| grep tty [ 0.000000] Kernel command line: root=PARTUUID=8884f2fe-d9ee-4bd1-93ad-99b6abb9fcf2 console=ttyS3,115200n8 earlycon=ns16550a,mmio32,0x02810000 mtdparts=47040000.spi.0:512k(ospi.tiboot3),2m(ospi.tispl),4m(ospi.u-boot),128k(ospi.env),128k(ospi.env.backup),1m(ospi.sysfw),64k(pru0-fw),64k(pru1-fw),64k(rtu0-fw),64k(rtu1-fw),-@8m(ospi.rootfs) rootwait [ 1.321385] 40a00000.serial: ttyS1 at MMIO 0x40a00000 (irq = 16, base_baud = 6000000) is a 8250 [ 1.331575] 2810000.serial: ttyS3 at MMIO 0x2810000 (irq = 24, base_baud = 3000000) is a 8250 [ 1.340363] printk: console [ttyS3] enabled [ 4.855949] systemd[1]: Created slice system-getty.slice. [ 4.958174] systemd[1]: Created slice system-serial\x2dgetty.slice. [ 7.666657] usb 1-1.4: cp210x converter now attached to ttyUSB0 [ 7.827091] usb 1-1.2: GSM modem (1-port) converter now attached to ttyUSB1 [ 7.851472] usb 1-1.2: GSM modem (1-port) converter now attached to ttyUSB2 [ 8.217625] usb 1-1.2: GSM modem (1-port) converter now attached to ttyUSB3 [ 8.404212] usb 1-1.2: GSM modem (1-port) converter now attached to ttyUSB4 So my rs485 port is /dev/ttyUSB0. Do use this in node-red ?

Suggestion To thank Quote Answer

9/13/2022 1:25 PM	Rate (0)
jmonzon Regular Member Joined: 6/15/2021 Last visit: 6/6/2023 Posts: 48 Rating: (0)	When I use that command I get: root@iot2050-debian:~# dmesg \| grep tty [ 0.000000] Kernel command line: root=PARTUUID=3056140f-a845-45fd-830a-93aa6a73bce3 console=ttyS3,115200n8 earlycon=ns16550a,mmio32,0x02810000 mtdparts=47040000.spi.0:512k(ospi.tiboot3),2m(ospi.tispl),4m(ospi.u-boot),128k(ospi.env),128k(ospi.env.backup),1m(ospi.sysfw),64k(pru0-fw),64k(pru1-fw),64k(rtu0-fw),64k(rtu1-fw),-@8m(ospi.rootfs) rootwait [ 1.335210] 40a00000.serial: ttyS1 at MMIO 0x40a00000 (irq = 16, base_baud = 6000000) is a 8250 [ 1.345437] 2810000.serial: ttyS3 at MMIO 0x2810000 (irq = 24, base_baud = 3000000) is a 8250 [ 1.354254] printk: console [ttyS3] enabled [ 4.547738] systemd[1]: Created slice system-getty.slice. [ 4.607015] systemd[1]: Created slice system-serial\x2dgetty.slice. [ 8.270298] usb 3-1.4: cp210x converter now attached to ttyUSB0 I also use ttyUSB0 in Node red This are the properties that I set in my PC config. The only parameter I change is the serial port Attachment Captura.PNG (609 Downloads)
	Last edited by: jmonzon at: 09/13/2022 13:29:26
Suggestion To thank Quote Answer

9/13/2022 1:35 PM	Rate (0)
rfond Advanced Member Joined: 6/8/2018 Last visit: 12/17/2024 Posts: 113 Rating: (5)	You change the pin on Sub-D9 ? serial PC use PIN 3 / 7 serial IOT use PIN 1 / 2 Attachment PIN.png (611 Downloads)
	Last edited by: rfond at: 09/13/2022 13:35:53
Suggestion To thank Quote Answer

9/13/2022 1:54 PM	Rate (0)
jmonzon Regular Member Joined: 6/15/2021 Last visit: 6/6/2023 Posts: 48 Rating: (0)	I use PIN 1 and 2. For PC I use a USB converter

Suggestion To thank Quote Answer

9/16/2022 7:08 AM	Rate (0)
jmonzon Regular Member Joined: 6/15/2021 Last visit: 6/6/2023 Posts: 48 Rating: (0)	After a lot of tries I reset the system with a new image. With the image I setup the pherical to read wit RTU 485 as @rfond said in this topic before. Everything works properly now. I can't imagine what the problem was with the old image... Thank you all for your help!

Suggestion To thank Quote Answer
This contribution was helpful to 2 thankful Users rfond apastore

|

Share this page:

Share this page on...

Related topics by keywords:

SIMATIC IOT2050 Hardware

Follow us on