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geekhack Projects => Making Stuff Together! => Topic started by: sheckta on Thu, 21 September 2017, 10:30:47

Title: seeking for a way to fit a teensy lc on a custom 105 key
Post by: sheckta on Thu, 21 September 2017, 10:30:47

hey i just purchased a ducky set of 109 keycaps but i will only use 105 of them and since i mentionned in the title i'd like to use a teensy lc but being totally new to all this i dunno how to go with the matrix because i'm limited to 25 pins...

if anyone out there could help me that would be awesome! thx by advance and hoping to talk to you soonish!!

PS: by the way here's the keycap set i'm talking about[attach=1]

edit: 104 keys not 105

Title: Re: seeking for a way to fit a teensy lc on a custom 105 key
Post by: Tactile on Thu, 21 September 2017, 11:16:13

There might be a better choice for your project. The Teensy LC requires 3.3 volt input on the I/O pins and is not 5 volt tolerant (https://www.pjrc.com/teensy/teensyLC.html). USB is 5 volts so you'd have to deal with that somehow, while other controllers can deal with 5 volts out of the box.

Title: Re: seeking for a way to fit a teensy lc on a custom 105 key
Post by: sheckta on Thu, 21 September 2017, 11:19:22

i already bought it :/ that's a problem...

Title: Re: seeking for a way to fit a teensy lc on a custom 105 key
Post by: rich1051414 on Sun, 24 September 2017, 14:50:58

Man, the teensy 2 and teensy 3.2 are 5v tolerate, but specifically the lc is not. I don't think the board uses much power, so you may be able to get away with a voltage divider to convert the 5v to 3.3v. A voltage divider is just two resistors.