How to pop up a Picoprobe from the Adafruit QT Py RP2040

A little while back I wrote about Adafruit’s QT Py RP2040 and how it makes a nice, compact Picoprobe. That’s a Raspberry Pi RP2040-based device used as a bridge between your computer and a target device for debugging work using Single Wire Debug (SWD). I first used the QT Py RP2040’s side-mounted GPIO pins, but SWD hosting is a great role for the device’s QT Stemma connector.

QT Py Rp2040 with its SWD-ready QT Stemma connector in black and RGB LED marked NEO
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Tackle async signal safety in Swift

How do you safely interrupt a command-line program written in Swift? This question was posed to me this week by a reader who got in touch to point out that boilerplate code included in my How to write macOS command line tools in Swift post might not be totally safe: it could leave a program and system in an undefined state, which is never a good thing. So I took a closer look.

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Celebrate the 40th anniversary of the Sinclair ZX81 with this multifunction-key-tastic T-shirt

Nearly half a century ago, Clive Sinclair’s Sinclair Research made history. It released the ZX81, one of the key home computers of the 1980s, as the first low-cost micro available to High Street shoppers. And you can express your love of early 80s tech with my latest retro-wear: the ZX81 keyboard shirt.

Modelled by yours truly
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Raspberry Pi Pico proxies: the Pimoroni Tiny 2040 and the Adafruit QT Py RP2040

Having spent some time with the Raspberry Pi Pico, I thought it was time to try out some of the other RP2040-based development boards that have become available. When it launched the Pico, the Raspberry Pi Foundation said it would make its RP2040 microcontroller available to third-party board makers. Retailers Pimoroni and Adafruit were among the first to toss their caps into the ring. Their offerings: respectively, the Tiny 2040 and the QT Py RP2040.

RP2040 boards: Pico (L), Tiny 2040 (TR) and QT Py RP2040 (BR)
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Looking for syntax highlighted QuickLook code previews? Look no further

I’d like to introduce you to the latest member of the PreviewApp family: PreviewCode, which provides syntax-coloured QuickLook previews and Finder icon thumbnails for over 50 programming languages, including Swift, Objective-C, C++, Rust, JavaScript and Python, and data file types for macOS. You can choose to preview your source code any of 100 dark and light themes.

Previewed code courtesy of PreviewCode
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Stay ahead of git with this sharp script

I work on quite a few git repositories at once, and I don’t always commit changes in one before making changes to another. Or if I do, I don’t always push the changes up straight away. That might not be best practice in software development, but hey, it’s what I do. The issue for me is remembering what state each repo is in. Here’s the script I use to tell me.

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MNU now supports Mac terminal emulator iTerm2

MNU, my macOS menu bar utility that lets you call up regularly used command line operations and more, now supports iTerm2, the popular alternative to macOS’ own Terminal app.

MNU in action
MNU in action
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Crop picture files with confidence and pixel-precise offsets, using sips and imageprep

I recently had a rather large number of screenshots to process: specifically to crop them down to a small area about a third of screen width in and two-thirds of its height down. I could have done this manually, but it’s easy enough to make mis-crops when you’re cropping a couple of images by eye, let alone a 100 or so. The solution? Get your Mac to do it for you. Here’s how.

imageprep 6.30
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