Simple station for monitoring environmental conditions in the lab over MQTT.
Based on the Bosch's BME280 humidity, pressure, and temperature sensor. Using Adafruit's breakout board.
Designed to work with mqtt.chem.wisc.edu.
This is an open source hardware project licensed under the CERN Open Hardware Licence Version 2 - Permissive. Please see the LICENSE file for the complete license.
This repository is being mirrored to several version control systems in an attempt to ensure maximum avaliability.
This PCB was designed using KiCAD version 5.
Refer to weather.pdf for schematic.
PCB images generated with tracespace follow.
| reference | value | manufacturer | part number | price | vendors |
|---|---|---|---|---|---|
| A1 | ESP8266 breakout | Adafruit | 2471 | $10.00 | Adafruit DigiKey |
| C1 | 100u | Illinois Cap. | 107KXM025M | $0.25 | DigiKey |
| C2 | 10u | Yageo | CC1206KKX7R8BB106 | $0.25 | DigiKey |
| C3 | 22u | Yageo | CC1206MKX7R7BB226 | $0.75 | DigiKey |
| C4, C5 | 1u | ||||
| D1, D2 | red LED | Lite-ON | LTST-C230KRKT | $0.50 | DigiKey |
| J1 | barrel jack | $1.00 | |||
| PS1 | VXO7805-500-M | $3.00 | |||
| Q1, Q2 | MOSFET N-ENH | Diodes Inc. | 2N7002K-7 | $0.25 | DigiKey Mouser |
| R1, R2 | 1k | ||||
| R3, R4, R7, R8 | 4.7k | ||||
| R5 | 470k | ||||
| R6, R9 | 1M | ||||
| U1 | BME280 breakout | Adafruit | 2652 | $20.00 | Adafruit DigiKey |
| U2 | counter | TI | CD4060BM96 | $0.50 |
All prices are extended. Assuming an order of 10 PCBs, the boards themselves should cost around $5 each.
This project uses micropython, specifically microhomie. Refer to the "firmware" directory in this repository for detailed instructions.
- value of C5
- new hour long reset timer based on CD4060BM96
- SOT23 packages for all discrete transistors
- initial design