WeatherDuino Forum

Hello folks,

I don't know if I'm in the right session.
I have a question for you if feasible.
The idea is to acquire the variable data provided by the RX software and to convert them (temperature value, humidity value, pressure value, etc.) into a 0-10V voltage signal in order to be used with a PLC unit. On the market I found this DAC device that convert the I2C bus into a 0-10V signal. https://store.ncd.io/product/1-channel-0-10v-dac-digital-analog-converter-i²c/   Since I need to convert 8 values, I need of 8 DAC; and since each converter has to be associated with a specific address as per each I2C device, I would like to know if the scratch loaded in microcontroller of the receiver still has space to insert these add instructions (also as microcontroller memory) or is it a totally unachievable idea?
I appreciate any answer or suggestion you can give me.

Kind regards
Bomben

Hi Bomben

It is hard to answer to your question. It isn't only a question if there is enough memory or not, more important than that is how long will take to execute the extra routines to accomplish your goal, how often they will run, etc...
In general the idea is: the more time the processor is executing whatever it is, the worst will be its capability to do its main job wich is receiving the RF signals.
Besides some general info, as you can imagine its difficult to me giving support to personalised system modifications, as each one may lead to unforeseen results on the way the system works.

Rgs
Werk_AG

Hi Bomben,

in addition to Werk's post concerning the used processing time I would propose the following solution:

You could modify the software of the receiver according to my data logging addon: https://www.meteocercal.info/forum/Threa...ging-addon
This feature is working properly and maintained by me and allowes you to send all the collected data each minute to the serial port.

Here you could introduce a co processing unit - e.g. an Arduino mega (or a derivate) to receive the data and convert it back to a 0-5V analog signal.
Then you have a lower resolution of the signal but you would not need additional devices or if you want the 0-10V solution you have at least enough space and execution time.

Regards,
Stefan

Thanks for your suggestions.  Perhaps the easiest solution is the one described by Stefan. Some time ago, I installed am Siemens PLC (Logo8) and all analog input ports work only with 0-10V or 4-20mA signals.  I'll definitely let you know how I'll handle it.   Thank you.   Very Respectfully Bomben

Hi Bomben,

It was good that Stefan was suggested his data logging add-on. I thought on it as possibly the best solution for your needs, however, because I'm not quite familiar with its use I haven't referred it.

Rgs.