Adding an LDR and DHT11 to my greenhouse monitoring project – light intensity, air temperature and humidity logged to emonCMS.
RFM12b to serial PCB for my Pi
A small home-made PCB that permanently fits the RFM12B-to-serial module on my Raspberry Pi – simpler than the native SPI efforts.
Stamp sized ATtiny84 remote sensor
A stamp sized ATtiny84 remote sensor – my version of Tobias’ Funky, a JeeNode Micro clone at a third of the size, 21mm across.
Using ATtiny 84’s internal temperature sensor
Reading the ATtiny84’s internal temperature sensor – no external parts, quite nice for a really low power node.
Power saving techniques for the Attiny84 powered TinySensor
Power saving techniques that let the ATtiny84 TinySensor run for months on a CR2032 – two months of room temperatures and counting.
Capture, decode and log to emoncms RFM12B packets on Raspberry Pi
Capturing RFM12B packets on the Raspberry Pi, decoding them and logging to emonCMS – the receiving side of my sensor network.
RF12 Demo sketch for ATtiny84
Porting JeeLabs’ RF12Demo sketch to the ATtiny84 – the TinySensor becomes a send/receive gateway on the Raspberry Pi’s UART.
Sending JeeLib compatible packets with ATtiny85 + RFM12B
Sending JeeLib compatible packets from an ATtiny85 + RFM12B by porting an old AVR library to the Arduino IDE – no Jeelib needed.
Experimenting with ATtiny85 + RFM12B
Getting an ATtiny85 to drive the RFM12B – 8 pins, 8KB flash, and enough for a working remote sensor unit.
Running the Attiny84 @ 4Mhz with the internal oscillator
Running the ATtiny84 at 4MHz on the internal oscillator – the lowest clock the RFM12B tolerates, chosen purely for the power savings.
Two-way serial communication between Raspberry Pi and a TinySensor
Two-way serial between the Raspberry Pi and a TinySensor – a NewSoftSerial patch adds the RX the tiny core never had.
Fix for TinySensor v1.3’s ISP connector
Fixing TinySensor v1.3’s broken ISP connector – a bodge wire beats pulling the ATtiny84 out of its socket every time.
Interfacing RFM12B to Raspberry Pi for cheap
Interfacing the RFM12B to the Raspberry Pi for cheap – a TinySensor on the Pi’s UART relays packets onward to emonCMS.
TinySensor PCB is ready
15 TinySensor v1.3 PCBs arrived – RFM12B works, the ISP connector doesn’t (my mistake), programming on a breadboard for now.
Got my Pi today
My Raspberry Pi finally arrived – from the February 29th sellout disappointment to a pre-order that actually shipped.
Measuring the solar yield
Measuring the actual solar yield of my evacuated tube collector and comparing it against the calculated available energy in emonCMS.
Thoughts on the Solar Energy Calculator
Refining the solar energy calculator – an emonCMS input processor now derives momentary yield from the tank temperature rise.
Calculating the available solar energy and logging it to emoncms
Calculating the Sun’s position and available solar energy for my 2.088m² evacuated tube collector, logged to emonCMS as a baseline.
TinySensor’s SD card power consumption worries (and solution)
The SD card was ruining TinySensor’s coin cell battery budget – measuring the sleep current problem and the fix.
Toying with ATTiny84 and SD card in Arduino IDE
Breadboarding the TinySensor v1.1’s ATtiny84 + SD card combo in the Arduino IDE before sending the PCB off to the fab.
The Tiny Sensor gets a SD card port
The TinySensor gets an SD card port – spare PCB space plus a few days of thinking before the first batch order.
Tiny Sensor plans
TinySensor plans: the ATtiny84 remote sensor goes to a real PCB fab – CR2032 slot, a JeeLabs compatible port, 15 boards minimum.
Single sided ATtiny84 temperature sensor PCB
A single sided ATtiny84 temperature sensor PCB after the double-sided fiasco – etches cleanly, sends every 60 seconds.
The ATtiny84 remote sensor gets and upgrade from single analog to multiple digital temperature sensors
The TMP36 tops out at 57°C on the ATtiny84’s 1.1V reference, so the solar tank sensor moves to multiple DS18B20s on one wire.
ATtiny84 remote temperature sensor with RFM12B
An ATtiny84 remote temperature sensor with RFM12B – JeeNode Micro envy turned into my own single-chip wireless node.
Controlling 433Mhz RF power sockets with a RFM12B module
Controlling 433MHz RF power sockets straight from an RFM12B module – appliance switching without wiring a single relay.
Sensing Shield #1 in action
Sensing Shield #1 installed at the breakers box – 9V AC/AC transformer in place, logging voltage, power factor and real power usage.
Software only solution for feeding weather data to emoncms
Feeding weather data to emonCMS with software only – no hardware, an online weather source covers humidity, pressure and wind.
RFM12B and Arduino Ethernet with WizNet5100 chip
Getting the RFM12B and an Arduino Ethernet (WizNet5100) to coexist on SPI – working around the nasty W5100 bus bug.