Linux Infrared How To: Chapter 3 Specific Connections and Protocols
I&#x27;ve gone down a rabbit hole from the microcontroller discussion a few days ago. I was thinking of various wireless communication methodologies (Bluetooth, Zigbee, WiFi, etc. etc.) when suddenly a link pointed out that IR &#x2F; TV Remote Controls were in fact wireless communications.<p>I began to look into it, and IrDA opened up my nostalgia. It reminded me of the simpler times in the 90s and 00s when PDAs, Gameboys, and even Tamagachi would communicate with each other with this infrared-light based protocols.<p>My dad even had infrared wireless headphones (to watch TV while my mom was sleeping). I&#x27;ve tried them back in the day, they were pretty reliable actually.<p>------<p>IrDA had some ambitions, you can see in this Linux HOWTO that there&#x27;s ways to set up networking stacks and far faster protocols (4MBit and 16Mbit) over this infrared communication stack. It looks like the IrDA group continued to make standards all the way up to 1 Gbps, but I don&#x27;t think it ever really became popular. Or maybe that was around the time Bluetooth started to take over?<p>For modern hobby electronic engineers, maybe IrDA still has a place? The lowest, simplest, layer of the IrDA protocol is FIR, a 115,200 baud almost-like UART protocol that is in fact, well supported in modern ATTiny, MSP430, and STM32 devices (!!!), with just a $4 led+phototransistor combo: <a href="https:&#x2F;&#x2F;www.digikey.com&#x2F;en&#x2F;products&#x2F;detail&#x2F;vishay-semiconductor-opto-division&#x2F;TFDU4101-TR3&#x2F;1681204" rel="nofollow">https:&#x2F;&#x2F;www.digikey.com&#x2F;en&#x2F;products&#x2F;detail&#x2F;vishay-semiconduc...</a><p>It seems like its just a UART that communicates over infrared light, maybe 10cm to 2 or 3 meters away reliably? I think TV Remotes can go even further (with the 38kHz TV Remote protocol), but IrDA&#x27;s UART is supremely flexible (indeed; UARTs are probably one of the easiest to use comms on these tiny microcontrollers).