Crossbar – The Fantastic DIY 4×4 LED Matrix

If you always have the intention to build a fantastic 4×4 LED Matrix, then you might want to check out this Crossbar! Well, this Crossbar is a very easy project, especially for those who involving with LED Matrix frequently. The Crossbar is based on a PIC16F628A. Although this chip cannot directly control the 16 lines necessary for an 8×8 matrix, but it’s more than enough to control the 4×4 matrix! One frame on a 4×4 matrix is only 16 bits or equivalent to 2 bytes, while a frame for an 8×8 matrix might require 8 bytes, which is 4 times of the 4×4 matrix did! If you want this Crossbar to be viewed by everyone, then you have to figure out the way to solder the LEDs at the intersection of each one. It’s better not to use the steel to hold the LEDs, as it easily rusted and has trouble holding onto the solder. By the way, you don’t need to use the LM7805 or any capacitor, if you applied a regulated power supply onto this project. Good luck… Continue reading

The Incredible Lego PICAXE Pete

You’re amazed by how capable the Lego PICAXE Pete moving and competing with each other? You want to challenge yourself to make a cool PICAXE Pete? If you have the urge here, then let started the project right now… First thing first, you might need to prepare these components: Two Lego 9V mini motors, which powered with 12V (The actuators/output devices) PICAXE 40X1 (The CPU) Two Li-Ion 7.2V packs in serial connection (The power source) Picaxe basic (The programming language) LDRs (The sensor/input devices) This PICAXE Pete is a homemade robot that has a line sensor, which using the light dependent resistors (LDRs) and a PICAXE-board with an L293 driver chip. The LM7805 voltage regulator is used for regulate the chips and line sensor with some bulk capacitors. Meanwhile, PICAXE board also has a means of connecting the programmer cable to the board, in order to program the PICAXE chip. There are two main parts for this PICAXE Pete, which as: The Engine block The tail section You need to put the engine block and the tail sections together; also… Continue reading