Arduino As ISP Programming Shield

isp_shield_topOne of the nice aspects of Arduino compatible hardware is the ease of program downloads. This is, in part, due to the bootloader that is programmed into the controller. How does that bootloader get on the hardware in the first place?

One answer is that a second Arduino can be used to load the bootloader (or any other stand-alone code) into the ‘virgin’ target hardware. The Arduino IDE includes an example program called ArduinoISP used for this, but it helps to have some supporting hardware. I built a shield with a few connections that speeds up the process of programming controllers.

Continue reading “Arduino As ISP Programming Shield”

Dual Voltage Power Supply

Dual_Supply 1Switching ‘buck converter’ power supply modules are fantastic, efficient, and can be bought for a few dollars (if not cents!). One drawback for me is that sometimes I need to have both positive and negative voltage supplies, and the buck converter/wall wart combination is not easily adapted to suit.

For these situations I have developed a reusable basic design using the LM317/LM337 3-Terminal Adjustable Voltage Regulators. Continue reading “Dual Voltage Power Supply”