Hardware abstraction layers

I feel as though I have been spending most of my CORNELIUS efforts on the ELIUS (language) part, and neglecting the CORN (operating system) part. Recently, though, I have been thinking about the notion of a “hardware abstraction layer” (HAL). This is a common part of many systems, and serves to isolate the messy, hardware-specific …

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Why is it so hard to build Raspberry Pi Linux drivers?

A few days ago I complained a bit about the profusion and confusion around the Linux drivers for the PiBorg LEDBorg multi-colour LED. With a bit of renewed energy, I thought I’d have a go at improving the situation by including a test for board revisionin the driver and ensuring that the correct GPIO pins …

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Controlling Raspberry Pi GPIO from Ruby

After my grumpiness yesterday, I thought I’d better strike out in a different direction while I consider my options with the various sub-projects I have on the go at the moment. I have mentioned before that I am a member of local Ruby user group “IPRUG”. This is on my mind at the moment as …

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Know any stackable, single Raspberry Pi GPIO connectors?

Yesterday, in my review of the LEDBorg, I wrote about how it can be inconvenient to connect two devices to the Raspberry Pi GPIO header at the same time, especially when one of them has a header which covers all the pins. I mostly write and run my own bare-metal software on the Raspberry Pi, …

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Hardware review: LEDBorg for Raspberry Pi

Introduction A while ago I ordered and received a LEDBorg bright, three-colour LED for my Raspberry Pi. I wanted to have a go at writing software to drive the GPIO pins, but didn’t want to go to the trouble of building my own hardware. Not only would that be fiddly, but if (when) something did …

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Morse code on a big, bright, LEDBorg

I have already proved to myself that I can set up and control the OK LED on the Raspberry PI board from a bare-metal C program, but I didn’t really feel that I entirely understood what was going on. The cop-and-paste code to set up and switch the GPIO line used for the OK LED …

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New Toys!

Aha! the new toys I ordered have arrived. Two new Raspberry Pi boards, two ModMyPi “gamble” cases, and some miscellaneous hardware. The two new Raspberry Pis are both 512MB “revision 2” boards with mounting holes, and I have already fixed them snugly in their new cases. The cases which arrived were black top/red bottom, and …

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