Posts made by tomkling

Hi Martin, thanks for the hint.
It said that there was a failure in the program. I deleted that part and now it compiles fine.

The port 502 is used for passing all data from and to the UniPi I/Os to EVOK, for example. The program that runs it is called unipitcp-server or similar and allows connection only from the UniPi itself. As far as I understand what you're using Mervis for, you could have also gotten the values directly from ModbusTCP on port 502 and then processed them in Python. This would have been probably a bit more difficult, because you would need to decode some values from Modbus' encoding and because you would need to know which register to use, but you can get this information from here: https://kb.unipi.technology/files:products:00-start
You need to choose your product line and download "Modbus Register map".

Hi there,
I'm trying to get data from the UniPi Axon M505 through ModbusTCP to a Weintek Display, which both work fine and shall be connected over Ethernet. The Easy Builder for Weintek Devices found the device and it is possible to edit the appearance, but you would need to configure a ModbusTCP channel to be able to transfer data between the two of them. The problem is that Mervis works while programming and has the UniPi connected, but says "build failed" after the compilation. I guess it would also be possible to start unipitcp with access for network devices, but I think this would be to big of a security risk and would rather like to configure a special channel with Mervis. Does someone know what's wrong with Mervis when it's not compiling and how to fix it?

Thanks in advance for the help.

Hi again and thanks for the help,
I've used ModbusTCP now and the input / output rates are much better, if someone's interested:
Reading only = 2,5 - 7,4 ms
Reading and Writing to another pin = 7 - 15 ms
Reading, Processing the measures, and Writing to another pin = 6 - 18 ms
I used Analog Input 2.1 / 2.2 and Analog Output 2.1 for my application

Hi Martin, thank's for the quick answer. I meant that I'd like to read the voltage when I wrote 'value'. What do you think, how fast could the voltage be read as I really need a reading interval lower than 5 ms for my application to work properly. I've seen that the MCP342x controllers could reach 240 SPS or some 4,16 ms interval time. Do you think this is possible or is there some kind of bottleneck in the communication?

Currently, I'm also trying to replicate EVOKs communication over the I2C bus to get the values directly. EVOK therefore uses Python Scripts and the pigpio module. If it's possible to reach the 240 SPS, that would be a good point to start for me, that's why I'm interested if it's possible in general to get that sampling speed.

Also, I've seen in an infographic that the Modbus interface is provided by EVOK. So is this faster than SysFs and the other EVOK interfaces or isn't it provided by EVOK but rather a standalone interface which makes it fast?
The Infographic: https://www.unipi.technology/upload/clanky/EVOK/EVOKedited.png

Hi everyone,
I've got an Axon M505 and I'd like to read values from the analog inputs ai_2_1 to ai_2_4 in under 5 ms. I tried using SysFS, but it was on average only 25 ms. Do you know a way to get this fast reading through EVOK or another interface on the UniPi?