I'm working with Arduino Mega and I'm trying to connect it with device for measuring temperature, wind speed etc. (it's Hot wire anemometer TMA-21HW). This device has RS232 protocol in manual.
I have made this connection:
Computer -> Arduino MEGA with RS232 host shield on it -> RS232 to USB adapter -> USB reduction (to connect two USB cabels with male ports...the reduction has on both side female ports) -> USB cabel -> my device
I have been strugling with this some time and I found out that the RS232 to USB adapter that I'm using is expecting host device on USB side. When I plug it to computer the little led on cable lights up and it's working (I tried).
So my question is....is there reduction RS232 to USB that works both ways? Or that there is host device connected on RS232 side and not USB side? My searching hasn't been successful yet...
I have tried to connect this device with USB host shield on Arduino but I don't know how to write code for it and what driver my device is using (those examples from USB host shield library didn't work for me and I'm lost...thats why I'm trying with RS232).
The RS232 shield I'm using:
Here in this topic I shared some more details about RS232 protocol of the device and cabels I'm using:
RS-232 is an electrical interface for serial communication that operates at ~ +/-12V. in other words you can't just connect the arduino serial pins to it, they need an rs-232 converter (e.g. max232). not sure if you have an RS-232 adapter on both the PC and Arduino
Please keep apart logical asynchronous serial communication by UART from TTL, USB, RS-232, RS-485 etc. physical line transmission. Converters for point-to-point communication typically work in both directions (full duplex), while multi-point bus nodes can not send and receive at the same time (half duplex) and can implement one direction only (RS-485...).