- Tue Apr 05, 2016 5:47 am
#44855
Hi,
Thanks for the reply. I guess the initial question was, on the ESP8266 does "Serial.xyz" code *share* across both the USB and the RX/TX pins, or is it dedicated to the USB console cable and you need to use another method to interface with the RX/TX pins. From what I can see, its shared.
Its TTL serial data thats streamed from a home ventilation system. It sends temperature readings from the roof and around the house to a display panel. I want to use an ESP8266 to capture that info and send to an MQTT broker to have displayed in Openhab (and then I can also run rules based on temperature readings) I can suss out the format of the data once I actually get *some form of data* streaming into the debug window (already found a web site where a guy has sussed some of that out) - but that's the issue at present, I'm not getting any data showing at all.
I think my issue with not getting data is my wiring - possibly a ground loop going on, although I can't work it out. I have the ESP8266 along with a TTL converter (because the home ventilation sends TTL data in 5V. It also sends and receives on the same wire) The ventilation system also provides 5V and GND via a couple of other wires that I'm tapping into. So I have the ventilation system 5V, GND and DATA going to the TTL converter 5V (high) side pins HV, GND and HV1 respectively. Then, on the 3.3V (low) side of the TTL I have 3.3V powered from the ESP, GND to the ESP and LV1 (data) going to the RX pin. I am not seeing any serial daa coming in at all. I've measured voltage at the TTL converter HV and GND and it seems to be ok, likewise with LV and GND, however I think I'm getting my GND wires crossed somewhere, maybe because the 3.3V GND side is also grounding through the USB ground? I'm not electronics savy enough to work it out.
Any ideas on the best way of wiring this up?
Cheers
Thanks for the reply. I guess the initial question was, on the ESP8266 does "Serial.xyz" code *share* across both the USB and the RX/TX pins, or is it dedicated to the USB console cable and you need to use another method to interface with the RX/TX pins. From what I can see, its shared.
Its TTL serial data thats streamed from a home ventilation system. It sends temperature readings from the roof and around the house to a display panel. I want to use an ESP8266 to capture that info and send to an MQTT broker to have displayed in Openhab (and then I can also run rules based on temperature readings) I can suss out the format of the data once I actually get *some form of data* streaming into the debug window (already found a web site where a guy has sussed some of that out) - but that's the issue at present, I'm not getting any data showing at all.
I think my issue with not getting data is my wiring - possibly a ground loop going on, although I can't work it out. I have the ESP8266 along with a TTL converter (because the home ventilation sends TTL data in 5V. It also sends and receives on the same wire) The ventilation system also provides 5V and GND via a couple of other wires that I'm tapping into. So I have the ventilation system 5V, GND and DATA going to the TTL converter 5V (high) side pins HV, GND and HV1 respectively. Then, on the 3.3V (low) side of the TTL I have 3.3V powered from the ESP, GND to the ESP and LV1 (data) going to the RX pin. I am not seeing any serial daa coming in at all. I've measured voltage at the TTL converter HV and GND and it seems to be ok, likewise with LV and GND, however I think I'm getting my GND wires crossed somewhere, maybe because the 3.3V GND side is also grounding through the USB ground? I'm not electronics savy enough to work it out.
Any ideas on the best way of wiring this up?
Cheers
