Reference Multi-sensor boards used in CubeCell and other Heltec Boards. ESP32, 151 etc.
I thought I would highlight to the group that the Multi-Sensor with the CCS-811 chip supplied from Chinese’s suppliers are supplied with "out of date firmware version normally 1.0.0 or 1.1.0.
These can be updated to V2.0.0 remove issues in the limitation of readings and update software.
The early version can be uprated from eTVOC max of 1156 bpm to:
• The equivalent CO2 (eCO2) output range from 400ppm up to 29206ppm.
• The equivalent Total Volatile Organic Compound (eTVOC) output range from 0ppb up to 32768ppb.
There is an excellent Github https://github.com/maarten-pennings/CCS81 that shows how to do the upgrade.I have tried this and works well both using ESP32 MCUs V1,V2 and also the CubeCell ASR65001 Modules , Capsules and Boards.
In the case of CubeCell as is even though it states it needs an ESP32 MCU it works well if there are some extra lines added in the basic sketch to enable the Vext power for the boards and if used enable the CCS-811 “wake up pin” where that is needed. ( Where WAKE pin is not connected to ground) . This can be added below to void Setup as shown :
void setup() {
pinMode(Vext,OUTPUT);
digitalWrite(Vext,LOW);
pinMode(GPIO0,OUTPUT);
digitalWrite(GPIO0,LOW);
delay(1000);
…
For the Heltec ESPv1 board there is no need to alter anything but for Heltec ESPv2 boards Lines will need to be added to turn on Vext if used such as:
void setup() {
pinMode(Vext, OUTPUT);
digitalWrite(Vext, LOW);
delay(1000);
…
Once updated to v2.0.0, The difference in the detected reading is drastic. As an example I sprayed some Spectacle cleaner in the air and I had readings above 20,000 ppb.
strong text
Good luck and enjoy
Simon 7/12/19