RAM ain’t RAM

RAM_ChipI have been meaning to look this up for a while.

Arduino programming means that at some stage you come across PROGMEM and EEPROM. While I understand in principle what these are, I wanted to get a more practical view of the memory in the Atmel processor in my Arduino Uno.

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A Software Algorithm for Solving Sudoku Puzzles

Soduko Puzzle
Soduko Puzzle

The classic Sudoku game is a number puzzle involving a grid of 81 squares, divided into into nine blocks, each containing nine squares.

French newspapers featured variations of the puzzles in the 19th century, but modern sudoku only started to become popularised in 1986 by the Japanese puzzle company Nikoli, under the name Sudoku, a contraction of the full name of the puzzle meaning single number in Japanese.

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Resistor Storage Solution

Resistor_box
Resistor Filing Box

I bought a through-hole ‘variety’ resistor pack from Amazon some time ago and received thousands of resistors from 1Ω through hundreds of MΩ. The problem became one of storing them in a way that made them accessible and easy to find the right value.

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MAX7219 and LED matrix power requirements

Parola_ModuleA recurring question is how much current Parola (and similar) modules use, and can how many can be directly powered from the Arduino 5V power supply. The answer is that it depends – but on what, exactly?

I thought I would try an experiment and actually measure the current usage and answer the question to my satisfaction. I used my Parola module (forum discussion) as the test device, but this is similar to the more generic modules and I believe the results are transferable.

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Having Fun

I enjoy writing libraries for the Arduino that other people can use to make their life easier. A few thousand downloads of the Parola library means that I get a lot of feedback on LED matrices. What is really interesting is being shown how ‘my baby’ is being used around the world!

Here is a varied collection of some of the hardware and software applications that I know about.

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