Re: Multiple esp8266 send/receive data to/from central RPi
Posted: Mon Mar 27, 2023 3:47 amThanks for all comments so far... Also received some comments on reddit on comparable question there.
To clarify some of the questions/remarks posted on my initial question:
Why not Wifi?
WiFi can't be used for communicating back to the central 'hub' since the Wifi chips are being used for scanning the Wifi environment
Distance
Distance will be cms apart (sensors vs central hub).
MQTT
MQTT is the messaging protocol on top of the (physical) communication layer. My question is mainly about this (physical) communication layer and how to best physically connect the sensors and the central hub. Once that is in place, the data sent over that connection might be through MQTT (preferably from my point of view, since gives most structure for me), but I think it depends heavily if MQTT transport can take place over that (phycial)communication layer or not. I have been using MQTT from ESP over WiFi/IP before and am familiar with the implementation. Not sure for example if such a communication protocol can also go over serial communication. ( I am planning on sending relevant datapoints back home over MQTT from the 'central hub' to the 'mothership')
Other thoughts
I am currently starting out with 'just' 2 sensors and linking them back over UART to a central hub. Initially the central hub will be ESP32 which has 3 UART ports as far as I have read. This 'hub' can then communicate back over WiFi itself to the 'mothership'
I am first planning on getting this working (got basic serial comms in place between two devices, now need to make sure I get the sensor readings/messages across consistently and without distortion).
Next step could be implementing some RTS/CTS or DTR/DSR variant to allow more 'sensors' to communicate back over UART. Probably need to implement some diodes then as well to prevent Tx sensor 1 --> Tx sensor 2 pin flows
Any thoughts on this might be welcome as well.
To clarify some of the questions/remarks posted on my initial question:
Why not Wifi?
WiFi can't be used for communicating back to the central 'hub' since the Wifi chips are being used for scanning the Wifi environment
Distance
Distance will be cms apart (sensors vs central hub).
MQTT
MQTT is the messaging protocol on top of the (physical) communication layer. My question is mainly about this (physical) communication layer and how to best physically connect the sensors and the central hub. Once that is in place, the data sent over that connection might be through MQTT (preferably from my point of view, since gives most structure for me), but I think it depends heavily if MQTT transport can take place over that (phycial)communication layer or not. I have been using MQTT from ESP over WiFi/IP before and am familiar with the implementation. Not sure for example if such a communication protocol can also go over serial communication. ( I am planning on sending relevant datapoints back home over MQTT from the 'central hub' to the 'mothership')
Other thoughts
I am currently starting out with 'just' 2 sensors and linking them back over UART to a central hub. Initially the central hub will be ESP32 which has 3 UART ports as far as I have read. This 'hub' can then communicate back over WiFi itself to the 'mothership'
I am first planning on getting this working (got basic serial comms in place between two devices, now need to make sure I get the sensor readings/messages across consistently and without distortion).
Next step could be implementing some RTS/CTS or DTR/DSR variant to allow more 'sensors' to communicate back over UART. Probably need to implement some diodes then as well to prevent Tx sensor 1 --> Tx sensor 2 pin flows
Any thoughts on this might be welcome as well.