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Homebrew ZIF ISP This morning I finished off the homebrew In System Programmer (ISP) that I started yesterday. It's now happily burning bootloaders onto the chips I'll be handing out on Monday's SPA session . I'm relieved to find that the installed code includes a blink sketch. That means that the Shrimp-builders will see that their new creations are working as soon as they power them on. I need to prepare 20 chips for the session, plus a couple of spares just in case. At this rate I'll be done by teatime.

I'm working on the preparations for my Monday evening Shrimping session at BCS SPA 2014 , and as always things are taking a little longer than planned. Phenoptix AVR ISP I got an AVR ISP shield from Phenoptix a while back and verified that it would program the chips I need for Monday. It has standard IC sockets, which means that you need to be a bit careful when removing the chips after you've burned the bootloader. If you don't do a straight pull you can bend the legs of the chip and the damage can make the chip unusable. I decided a few days ago that I'd use a Zero Insertion Force (ZIF) socket for the programming. These allow you to drop a chip in, close the gripper of the ZIF, program the chip and then release it. You can then remove the chip easily without any risk of damage. ZIF Socket It's a ZIF socket, Jim, but not as we know it I got a couple of sockets which were surprisingly hard to find in the UK. When they arrived I discovered that they ...

There's a revolution underway in Computer Science education. The Raspberry Pi has generated a huge amount of energy and enthusiasm, but there's also a lot of interesting activity around the Arduino. One great Arduino resource is the Shrimp, a low-cost compatible design aimed at educators and hobbyists with limited budgets. Landing the Shrimp You can find out more on the Shrimping It  blog. It describes ' the Shrimp  – a substitute for the Arduino Uno, which can be constructed for about a tenth of the price of the official board, shown here in stripboard and breadboard versions.' Note the absence of a PCB version! That's deliberate: the idea is that you will lean more, and feel more of a sense of ownership, if you have constructed the shrimp from scratch. That makes sense but I can see two situations where shrimp-catchers might prefer a PCB to work with. Some beginners starting out on their own might feel more confident building a PC...

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...