Archive for the ‘PIC16F690’ category

January 7th, 2015

A big surprise this morning – checking my magnetometer‘s logs I found that it had recorded the strongest magnetic storm since it was built in December 2011:

Magnetic storm on Jan 7, 2015

The weird thing is that the storm was completely unexpected! It’s like hearing a sunny weather forecast and getting the biggest snowstorm in years instead.

The explanation? says:

UNEXPECTED GEOMAGNETIC STORM: A strong G3-class geomagnetic storm erupted during the early hours of Jan. 7th, sparking bright auroras around Earth’s poles. What happened? The interplanetary magnetic field (IMF) near our planet tipped south, opening a crack in Earth’s magnetosphere. Solar wind poured in to fuel the strongest magnetic storm since Sept. 2014. NOAA analysts believe the fluctuation in IMF is related to the arrival of a CME originally expected to miss Earth.

Solar Wind

December 7th, 2014

Checking my magnetometer today I found this beautiful record.  Last night the Earth entered a fast moving (~700 km/s according to ACE) stream of solar wind. The wind’s buffeting of the magnetosphere is visible as a sudden increase of the noise around 14:40 UTC.2014_12_07_12_00_00


Surprisingly strong magnetic storms

February 20th, 2014



The CME impacts from the last two days sparked a decent magnetic storm. The magnetometer has gone bananas! On Feb 20, at ~11:30 UTC it went off the scale – for first time in years.


UV Exposure Card

October 3rd, 2013

Somebody used my countown timer project to create UV exposure card:

Very nice work on the PCB!

Here is another video, showing the timer controlling a lamp:

Another magnetic storm

October 3rd, 2013
Magnetogram recording

Magnetic storm, Oct 2, 2013

Last night my DIY magnetometer recorded another very nice magnetic storm. The initial CME impact arrived just on schedule (as predicted by NASA), shortly before 2am UTC. You can also see the impact of a second CME front shortly after 4:30am UTC.

For real-time data, check this page.

Another magnetic storm

June 1st, 2013

A good record of tonight’s G2 magnetic storm recorded by my home-made magnetometer:

Audio of a Mag 5.7 Earthquake

May 23rd, 2013

Today I managed to get a recording of a Mag 5.7 earthquake 206 miles (331 km) away. If you have headphones handy, put them on and listen to the sound of the earthquake. Headphones or good speakers are recommended because the frequencies are quite low.

The data comes as a side effect of the design of a home-made magnetometer I operate. When there is an earthquake nearby, the mirror starts swinging – this messes up the magnetometer record, but can be used to detect earthquakes quite far from here.

PIC Microcontroller Data Logger with Serial Interface

September 26th, 2011
PIC microcontroller based data logger with serial interface

Data logger


Some time ago I completed a data logger project and finally found time to document it and put the description online. The device amplifies and filters the analog signal from a sensor, then using a PIC microcontroller the data is digitized, encoded, and sent over serial (RS-232) interface to a computer. The project also includes scripts for processing and visualizing the data.

[ Go to project ]

PIC Microcontrollers: Multibyte math code generator for 8-bit PIC microcontrollers

October 27th, 2010
Multibyte math library for PIC microcontrollers

PIC Math

That last post (about the pulse-width modulation code generator) reminded me that I have another PIC mocrocontroller code generator to write about.  This one is for creating a customized multibyte arithmetic library. The library lets you add, subtract, multiply, divide, find modulus (remainder from division), compare, increase/decrease by one, and roll multibyte numbers – all in assembly language.  Just specify the precision (number of bytes), select only those operations that you need, and press a button to get the assembly code. Comes handly for a number of projects.

[ Go to project ]

PIC PWM Calculator & Code Generator

October 27th, 2010
PWM code calculator

PWM code calculator

Unless I’m missing something, this is not exactly a “code generator” despite what the site’s title claims. The C code is there, already generated, and the calculator generates some values for some registers based on the user’s input for the microcontroller clock frequency, desired PWM frequency, and PWM duty cycle. Generator or not, can still be quite useful.

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