Let's Make Robots!

QRD1114 digital output

converts analog output to digital one



Back again with some info... So I want to hit it in the middle...


Everyone who bulit a line follower sometimes get annoyed by the thing that his sensor returned an analog value and it was a pain in the "shoulder" to make it to get a good reading... I know AVRs need time to make conversion etc but why would you keep the MCU draining power etc when you can get a simple digital value back... Seriously, digital value with QRD1114...


    What you need to do is just attach 3 type of resistors... 1 is for sure to don't blow the IR led... but the other two are needed as one for pull-up and 1 for limiting current into the MCU...


The cap can vary from 0.01uF to 0.1uF sorry for this :D everywhere is 0.01uF I wrote 0.1 but its working too

As you see it's not a pain now to work with simple 1 and 0... Now I ask... better add 2 resistor in plus and a cap... or stay and eat your hat with programming?


Thats it guys, I know it's not hard or you can just google up and search etc... but why would you that?



I got the ideea from the guy who made the video too so all credtis goes to him... I just poested this as a post and ad him all the credits...


Thanks to OITRC



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Hehe, just don't forget there's always a trade-off somewhere, but it's good to know a few different tricks that can be used in the right situations =)

ah... I hope you never mind if I make a short about this little discusion and post it on my blog? :D

Not at all, LMR is for everyone =)

yeah :D now I'm thinking on the code... ;))


DDRB = output;

DDRB = high;


DDRB = input;

if(pinb1 == 1)

    sensor1 = 0;


    sensor 1 = 1;

if(pinb2... etc etc



should work :D I think, with sharing the same pin :D

Nice! All I need is digital from my QRD. Great tip!

I wonder if that can be used with simple IR LEDs

you are welcome :) this reduce the cost and developboard of LM394 needed for digital conversion... :) I use it in my new robot... will post it tomorrow