Vasilis Serasidis has been treating us with a bunch of cool projects. So here is another one worth attention. This time He’s built a four channel logic analyzer based on AVR Atmega8 microcontroller. He wanted it to be small and simple so everyone could replicate with no significant effort.
As output device he has chosen Nokia 5110 graphical LCD where all four channels are nicely seen with some timing grid. Logical analyzer is capable of capturing signals up to 400kHz with amplitudes up to 5V. Initial MCU storage allows buffering from 3.7ms (high speed signals) to 36s (low speed signals) signal that can be viewed, zoomed with one of three push buttons. Board size is 55×65 mm. This is really handy device to have in your backpack
Jonathan attended FOSDEM 2012 event with his custom made name badge and shared some details of it. This is simple and straight forward design based on MSP430F5171 16-bit microcontroller that controls 5×8 LEDs where the name is scrolled.
LEDs are connected in rows and columns, so five and eight pins of MCU are occupied. No limiting resistors or any transistors are used as leds are driven dynamically. Badge is powered with 3V lithium coin cell. PCB is double side and home made. Jonathan used toner transfer method for this and results are great. 6 mil tracks look really great. After tryout he suggests to add more LEDs to get better resolution as 5×8 is pretty hard to read. Anyway this is great way to stand out in a crowd.
Not all signal generators have to be complex devices. Sometimes you just need a signal generator with few features. This Attiny25 based signal generator does just that. It can output square, sine and triangle waves simultaneously from 1Hz up to 40kHz. Resolution isn’t brilliant – just 6 bits.
Signal frequency can be adjusted in 256 steps what means that from 1Hz to 40kHz it ups exponentially. Despite its poor signal quality and lack of fine control signal generator may find its purpose in many uses.
Attiny85 are 8 pin microcontrollers so they are perfect for small projects. Chris had few of these lying around and decided to build fast and simple prototyping board. He made a project layout with KiCAD and instead of etching PCB he simply soldered it on prototyping board.
He’s programming Attiny85 using Pololu AVRISP v2 programmer and Arduino. So this is simple set up to test things out where or make a complete project.