{"id":118,"date":"2011-12-05T09:39:12","date_gmt":"2011-12-05T09:39:12","guid":{"rendered":"https:\/\/howiem.org\/wordpress\/?p=118"},"modified":"2011-12-05T09:39:12","modified_gmt":"2011-12-05T09:39:12","slug":"diy-atmega-programming-clip","status":"publish","type":"post","link":"https:\/\/howiem.org\/wordpress\/2011\/12\/05\/diy-atmega-programming-clip\/","title":{"rendered":"DIY Atmega programming clip"},"content":{"rendered":"

Picked up one of these IC test clips on eBay for a few quid. It makes a spectacularly convenient programming clip.
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\"IMG_1154\"<\/a>
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\nThe idea is that you clip it to a chip on a circuit board so you have easy access to the connections for use with test probes.
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\nI’ve got a different use for it though. If you develop a circuit using an Atmega chip (like, say, a circuit you developed with an Arduino but have now moved to a custom board), reprogramming the chip is fiddly. The best way to make your circuit easily re-programmable is to build an ISP header onto your board – it’s just a 6-pin connector that lets you blast new programming onto the chip without removing it from the circuit.
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\nMost of my little circuits don’t have room for the 6 pin connector though, and it’s a hassle to hook up the 6-pin programming connections when you’ll hopefully never have to reprogram the things anyway.
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\nTo program the chips on these boards you have to lever the chip out, stick it in a programmer and then stuff it back into the circuit board again. Not the most difficult thing to do, but it can get a bit fiddly, and it’s always a bit dangerous trying to lever the chip out without damaging the chip or the board. The test clip fits over all the pins you need access to for programming though – this clip doesn’t reach the bottom four pins on the chip:
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\n…but it turns out you don’t need to use those pins for programming. So: I dug out a bit of ribbon cable with a 6-way pin header on the end:
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\nStripped the wires (carefully – they’re bloody thin conductors in ribbon cable):
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\n… and soldered the wires to the right places on the test clip:
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\nA bit of heatshrink tubing makes it all look slightly more perfeshional:
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\nAnd lo – it’s now a programming clip, letting you reprogram the chip without having to pull the chip.
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\nHandy.<\/p>\n","protected":false},"excerpt":{"rendered":"

Picked up one of these IC test clips on eBay for a few quid. It makes a spectacularly convenient programming clip.<\/p>\n","protected":false},"author":2,"featured_media":108,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[5],"tags":[],"class_list":{"0":"post-118","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-electronics-and-hackery"},"_links":{"self":[{"href":"https:\/\/howiem.org\/wordpress\/wp-json\/wp\/v2\/posts\/118","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/howiem.org\/wordpress\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/howiem.org\/wordpress\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/howiem.org\/wordpress\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/howiem.org\/wordpress\/wp-json\/wp\/v2\/comments?post=118"}],"version-history":[{"count":0,"href":"https:\/\/howiem.org\/wordpress\/wp-json\/wp\/v2\/posts\/118\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/howiem.org\/wordpress\/wp-json\/"}],"wp:attachment":[{"href":"https:\/\/howiem.org\/wordpress\/wp-json\/wp\/v2\/media?parent=118"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/howiem.org\/wordpress\/wp-json\/wp\/v2\/categories?post=118"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/howiem.org\/wordpress\/wp-json\/wp\/v2\/tags?post=118"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}