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 (https://wiki.teltonika.lt/view/GPL).
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.
software engineer of INNOVINNPROM,
P.S.: Image for interest (КДПВ)