@Dimitrios noted something very important in the comments to an earlier my post on low-power sketch: One of the things I noticed when I started playing with the RFM12B module was that the receiver front end was mostly overloaded by…
Temperature to color encoding for visual status display using RGB LED
I sometimes need to quickly check on certain temperature reading and find myself walking to one of my status displays to see, for example, if there will be enough solar hot water for a hot tub. I figured, it would…
Optimizing DS18B20 code for low power applications
I have been uneasy with the conversion time that the DS18B20 temperature sensors have, it is 750 ms when using the 12-bit resolution: The 12-bit resolution is the default power-on, so when powering the sensor from a digital pin, you…
Miniature OLED status display with Funky v2
I purchased a small serial OLED display few weeks ago, it showed up yesterday at the mail box. Dimensions of the PCB are (WxHxD):30x28x4.8mm (1.2X1.1×0.19″) and the display itself is 22x12mm with 128×64 pixels. Pixels are really bright and viewing…
DHT22 accuracy test part 2/2
I have measured the relative humidity as per my set up, and got steady readouts exactly in the 75% area as expected: DHT22 Library Demo Requesting data…Got Data 25.50C 75.20% Integer-only reading: Temperature 25.5 C, Humidity 75.2 % RH Requesting…
I already mentioned, that I have a small RFM12B ‘shield’ that can be used instead of the nRF24L01+ on a WorkerB!. I put one to a test today, all working as expected: This makes it easy to…
DHT22 accuracy test part 1
I have been boggled for a while about the Relative Humidity data that I gather, I get some higher than expected reading. I blogged about this in this post and @Dimitrios suggested in the comments that my box my be…
nRF24L01+ range testing
I did some range testing earlier today, using a ping-pong pair of sketches uploaded to a WorkerB! and a Dirt Cheap Low Power Wireless Sensor Node: This works by sending an incrementing value (millis’ value) every second, and the…
The WorkerB!
I have received 5 test PCBs today of the unnamed ‘ATMega32u4+nRF24L01’ board project that I described earlier, I decided to call it a ‘Worker Bee’ or WorkerB! as its task will be to collect and transmit data. The final PCB layout…
3D printed Stevenson screen
@Dimitrios commented the other day on my Funky+DHT22 post that my readings seem to have a lot of 99.9% relative humidity readouts and suggested that it may be due to the black box that I enclosed the project. I do…
Texas Instruments SimpleLink CC3000 WiFi Module
There is a relatively new product by Texas Instruments – the SimpleLink CC3000 WiFi module that is quite small and cheap – $12. Looks quite promising, size is about as much as a fingernail: There is a KickStarter project using…
Cheap DIY power monitor
My father asked me to create a standalone power monitor for him, he’d like attach it to some appliance and see its momentary and accumulated over time power consumption. Using OpenEnergyMonitor’s resources that was an easy task to do. I…
7 months of sending and still going
My Funky+DS18B20 temperature logging project is still running on that same CR2032 battery ever since my original post back in Oct 31st 2012, that makes it 7 months of run time so far. I have a live chart here: It…
Logging manualy entered values to emonCMS using keypad
I have finally found some time today to put my keypad project into work, namely I decided to use it for weight logging project here a home. The idea is simple: take measurement using the bathroom scale, then punch in…
Running on ‘dead’ batteries
I have a load of used AA/AAA batteries (0.9-1.2V), that I keep to run my LTC-3525 enabled projects like Funky v1 and v2; however the LTC-3525 will work down to 0.8V so the batteries are declared ‘dead’ for a second…