ESP01 Fine Particulate Logging


A Very Low Cost Serial to WiFi Interface.

Even though you really can't see much, the top image is a remote located Honeywell HPM PM2.5 particulate sensor. Window screen mesh keeps large debris and insects from entering the small sensor.

The second and third images show how an ESP01 provides data logging to a host server without needing to add an additional power source or modify the Dylos. The small enclosure contains the ESP01, a TTL to RS232 converter a DC to DC power supply. All parts acquired form Ebay. The Dylos wall-wart supply plugs into the small comm box and a daisy-chain patch cable then plugs into the Dylos.

While the host simply collects and logs the Dylos serial data, the first example using the HPM sensor is a little more complicated. For the HPM sensor, the host receives the raw binary comm message which has to be validated and processed before logging occurs.

In both of these examples the ESP01, using the default firmware, is operating in pass-through mode and is configured using a single Python script.