RAREblog

is your brainchild going to work? You've built your latest (or maybe your first) Arduino clone. It might be breadboarded , on stripboard , or a PCB . You've visually checked the connections, over and over, and maybe done some quick continuity checks with a multimeter. Everything looks fine. But will it actually work? Follow these steps to check it out. Use blink - The Secret Sauce Here's my secret sauce for building testable clones: Use a chip that has both a bootloader and the standard blink sketch pre-loaded . Use a 5V LED for testing. Let's look at those in a bit more detail. Use a chip that has both a bootloader and the standard blink sketch pre-loaded When you test your clone with a pre-prepared chip, you're starting with a known good core component. If the blighter doesn't blink you know you've made a mistake in the wiring. For more detail on why this is a goo idea on courses, see here . A 5v LED is the tester's friend Many make...

Yesterday I assembled and tested the phenoptix AVR ISP Shield . Here's what I found out while trying it out. First, a bit of background. I needed to build a batch of low-cost Arduino clones. In the past I've bought basic DIY kits from oomlout which include pre-programmed chips, but this time I wanted to keep the cost as low as possible. That meant I needed to buy chips without a boot-loader (as mentioned in yesterday's post)  and then install the boot-loader myself, using an existing Arduino as an In-System Programmer (ISP). I've done that before using a breadboard, some jumper wires and a handful of extra components.  It's a fiddly process and easy to get wrong. This time I decided to get an ISP shield designed for the purpose. It added a little to the cost, but I though it would save time and money in the future and it was fun building it :) There are lots of Arduino ISP shields on the market, including models from Adafruit and SparkFun . I decided to go wi...