Terminal 28

The first thought that came to my mind when I read that was: “wow, that’s a remarkably complicated-sounding name for a simple blog post”. I’m looking for replacements, so please drop a few in the comments. Anyway, back to business. The point of this post is to outline the procedures involved in using nRF24 radios (by now, you’ve realized I must really like them ) on a Raspberry Pi via a bitbanged SPI connection. Normally, you’d simply compile and install Tmrh20’s RF24 library, wire up the module the Pi’s dedicated SPI pins, and then go forth from there. However in my last post, there was the possibility that the hardware/dedicated SPI pins would be used for some other purpose ( oh I don’t know, providing wired ethernet maybe? ) and would be unavailable to do this. I then talked about the moderately-involved process of providing a software-based/bitbanged SPI peripheral which could then be used for some other purpose. This post aims to illustrate one such possibility. The RF24 librar...

Hello all and happy holidays to everyone! I’m taking a break off work for the holidays so I have a little bit of time on my hands. I will therefore regale you with tales of my exploits! From my last post, I talked about the somewhat “edge” case where you’d want to add (cheap) Ethernet to a Raspberry Pi, probably the A+ or Zero as the case may be. I haven’t figured out the fixed MAC thing just yet, but I’m working on it. Anyways, after some time, another edge-edge case came to me: The ENC28J60 takes up the only SPI peripheral available on the Pi, so what if you needed to use both the ENC28J60 AND some other SPI device? The Pi’s SPI peripheral has two chip selects, so it is theoretically possible to use the exact same bus while using the first chip select for the ENC28J60 (which it uses by default) and using the second chip select for the other device. However, it goes without saying that network communications require some serious computing firepower so it might cause a bit of a perfo...