Difference between revisions of "Wireless Weather Sensors"
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== Status == | == Status == | ||
<onlyinclude>{{{status|In progress}}}</onlyinclude> | <onlyinclude>{{{status|In progress}}}</onlyinclude> | ||
| + | |||
| + | == Operation == | ||
| + | * Each unit will power up and listen for the sync signal from the master unit. | ||
| + | * Once they get the sync signal, they listen for any other already established units to send their data. | ||
| + | * Then they locate the next spot in the time slots. | ||
| + | * Something about collisions | ||
| + | * Something about the master allocating timeslots dynamically | ||
| + | * Something about filling in blank timeslots. | ||
| + | |||
| + | == Assembly == | ||
| + | === Slave === | ||
| + | * A slave has all of the parts below | ||
| + | |||
| + | === Master === | ||
| + | * A master has all of the same parts | ||
| + | * A master also piggybacks on an openmesh router or 802.11 device of some sort. | ||
== Parts == | == Parts == | ||
Revision as of 14:52, 4 February 2011
Contents
[hide]Overview
Designed to be simple to build, low parts cost, and low maintenance.
Needs:
- Wirelessly transmit temperature and relative humidity to a main unit.
- Run off a single AA, two AA, or a 9v battery
Wants:
- Two pins who's grounded status could be reported (think a door sensor, or something)
- Two pins that could be set to send 3.3v or 5v to run an relay
- Thermostat control?
Status
In progress
Operation
- Each unit will power up and listen for the sync signal from the master unit.
- Once they get the sync signal, they listen for any other already established units to send their data.
- Then they locate the next spot in the time slots.
- Something about collisions
- Something about the master allocating timeslots dynamically
- Something about filling in blank timeslots.
Assembly
Slave
- A slave has all of the parts below
Master
- A master has all of the same parts
- A master also piggybacks on an openmesh router or 802.11 device of some sort.
Parts
| Name | Price for 10 units | AVR pins required | Link | Alt Link |
|---|---|---|---|---|
| RFM22B-S2 Wireless Transceiver | $4.40 | 4(SPI) | http://www.hoperf.com/rf_fsk/RFM22B.htm | |
| DHT22 Humidity and Temperature Sensor | $8.96 | 1 (i think) | http://www.sparkfun.com/products/10167 | |
| Pressure Sensor | ? | ? | ? | |
| Battery case | ? | ? | ? |
AVR possibilites:
| Model | I/O Pins | Price per 10 | Link |
|---|---|---|---|
| ATTINY84 | 12 | $3.01 | http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=ATTINY84-20PU-ND |
| ATTINY4313 | 18 | $2.80 | http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=ATTINY4313-PU-ND |
