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I want to build a clock!
Moderators: adafruit_support_bill, adafruit

Please be positive and constructive with your questions and comments.

I want to build a clock!

by badbarky on Thu Jan 31, 2019 3:34 pm

Hey folks. I’m new to tinkering with projects like this and get scared when I see things like ‘attach to gpio’ or ‘search github’. Anyways I have a 7 segment display #812 from adafruit, a couple of trinket m0s, a Gemma, circuit playground, and rpi zeros. What is the best way to get a clock running? I teach elementary technology and I want to have it as a desk clock. I’ll probably house it in some of the wooden boards my daughter has been breaking in taekwondo! Thanks in advance.

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Re: I want to build a clock!

by adafruit_support_bill on Thu Jan 31, 2019 4:59 pm

Driving that display directly requires a lot of GPIO pins. You can simplify things greatly by using one of these: https://www.adafruit.com/product/877
That lets you drive the display with the i2c bus which requires only 2 pins. There is also a library for it to make the coding simpler as well.

Here is a simple clock project based on that display and backpack. You can substitute the M0 Trinket for the Metro. The RTC module is optional. But you can expect quite a bit of drift using the internal clock on the Trinket (or just about any microcontroller for that matter).

https://learn.adafruit.com/metro-minima ... ck-circuit

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Please be positive and constructive with your questions and comments.