subscribe to our Youtube


14455 questions

17168 answers


0 members

We are migrating to our new platform at Moving forward, you can continue discussions on this new platform. This current platform will be temporarily maintained for reference purposes.
+6 votes
1,847 views 2 comments
by anonymous

Hello, I am software engineer from ukrainian company "INNOVINNPROM".

We developed device with Modbus RTU serial interface. It will be used on enterprises to collect data of some measurements. New data available in our device every 100 ms.

We made experiment with 32 our devices and industrial PLC (M241 by Schneider Electric) in Modbus Master role. We collected data from all devices approximately in 1 second.

We need to send collected data to our servers by internet but industrial PLCs cant do this securely. SSL, VPN, HTTPS, MQTTS is not option of PLC.

After firmware release RUT9XX_R_00.06.04 | 2019.07.24 for RUT955 router with modbus serial master. We bought one and start experiments.

Everything is great. Teltonika RUT OS is highly configurable. We have options of VPN and http(s) or mqtt(s) variants to send data. But minimum collection time is 1 minute. It is awful.

We also notised that firmware of your devices based on OpenWRT.

I have personal expirience with OpenWRT and SOHO routers since 12.09 (Attitude Adjustment). So i downloaded latest SDK from GPL section of your site (

I made test build and flash result firmware image quickly.

After that I analyzed SDK and understood that many of Teltonika`s components distributed in binary form in package "base-files" (package/base-files/files in SDK archive). And sources are unavailable.

So I can`t make quick patch for "package/base-files/files/usr/sbin/modbus_serial_master".

So we have 3 questions.

1. Is it worth to wait improvements from Teltonika`s developers in modbus_serial_master to set data polling period in seconds or even in milliseconds (It will be enough to start from 100ms)?

2. If we decide to make own implementation of modbus serial master (and modbus data sender), what about licensing: do we need publish our sources and changes? Due to Teltonika`s rights and 3rdparty GPL`s (and other licenses) rights?

3. Is it possible for Teltonika to publish sources of modbus_serial_master and modbus_data_sender? We will make improvements and return in to upstream.

Best Regards,

Alexey Bondarchuk

software engineer of INNOVINNPROM,

Ukraine, Vinnitsya.

P.S.: Image for interest (КДПВ)

by anonymous
Hello Alexey,

Regarding the 1st question, our RnD has already made improvements for the Modbus data polling functionality to poll data every second instead of minute.

Firmware with these changes will be released at the beginning of next week and will be available for downloads from our wiki page:
Hello Martynas,

Have you improve pooling interval in modbus serial and tcp master ? We have same issue like Alexey, but in modbus_tcp_master module.

2 Answers

0 votes
by anonymous

For this case try to contact with Teltonika directly:
0 votes
Hi Alexey,

Happy to see a SE PLC customer. If you want to send data over Internet by https or mqtt, Schneider have released Modicom M262 with TLS management.

Hope it could help you.