I purchased a ChronoDot and 4-Digit 7-Segment Display so that I can display the time for a project. Both are I2C devices.
The Display is connected to the A4 and A5 pins on my Arduino UNO.
However, A4 and A5 are also where I am supposed to attach the SDA and SCL respectively for the ChronoDot RTC.
How do I wire up my breadboard for this? I have studied the I2C protocol and have the understanding that I can connect multiple slaves.
Chronodot with 4-Digit 7-Segment Display
Moderators: adafruit_support_bill, adafruit
Please be positive and constructive with your questions and comments.
- marke3
- Posts: 205
- Joined: Sat Feb 08, 2014 5:24 pm
Re: Chronodot with 4-Digit 7-Segment Display
That's right. The same two pins. Each I2C device has its own address so can use the same bus. You'll see the addresses in the example code.
- ilovetofu
- Posts: 35
- Joined: Sat Aug 22, 2015 1:38 am
Re: Chronodot with 4-Digit 7-Segment Display
Thanks marke3, works like a charm.
I don't think the 4-Digit 7-Segment display has an address select pin, so I gather the slave address is pre-set. What would I do if I wanted to add 3 of these displays onto my breadboard to work with the Arduino?
Also, when reading the I2C specs and the ChronoDot info, they advise using pull-up resistors with the ChronoDot IF your controller doesn't already implement them. At the moment I have not added any resistors to the circuit. Should I be adding them in the case of Arduino Uno?
I don't think the 4-Digit 7-Segment display has an address select pin, so I gather the slave address is pre-set. What would I do if I wanted to add 3 of these displays onto my breadboard to work with the Arduino?
Also, when reading the I2C specs and the ChronoDot info, they advise using pull-up resistors with the ChronoDot IF your controller doesn't already implement them. At the moment I have not added any resistors to the circuit. Should I be adding them in the case of Arduino Uno?
- marke3
- Posts: 205
- Joined: Sat Feb 08, 2014 5:24 pm
Re: Chronodot with 4-Digit 7-Segment Display
The display backpack has some pads for solder jumpers to set alternate addresses and that would let you do multiple displays. Instructions here: https://learn.adafruit.com/adafruit-led ... 2c-address
I'm pretty sure all Adafruit boards, including that backpack, include the pull-up resistors so using the chronodot with the Adafruit display backpack will have you covered as they will act on the same shared data and clock lines.
I'm pretty sure all Adafruit boards, including that backpack, include the pull-up resistors so using the chronodot with the Adafruit display backpack will have you covered as they will act on the same shared data and clock lines.
- ilovetofu
- Posts: 35
- Joined: Sat Aug 22, 2015 1:38 am
Re: Chronodot with 4-Digit 7-Segment Display
thanks for the link marke3, that seems pretty straightforward.
- brennerh
- Posts: 1
- Joined: Sun Aug 30, 2015 1:31 am
Re: Chronodot with 4-Digit 7-Segment Display
do you know how to code the 7 segment display for an RTC chip?
- marke3
- Posts: 205
- Joined: Sat Feb 08, 2014 5:24 pm
Re: Chronodot with 4-Digit 7-Segment Display
Which parts do you have? The tutorials for those should have lots of guidance.
- ilovetofu
- Posts: 35
- Joined: Sat Aug 22, 2015 1:38 am
Re: Chronodot with 4-Digit 7-Segment Display
marke3: yes thanks for the link, I can see how to change the address now.
brennerh: yes, I managed to initialise the RTC, read the date/time and display the time to the 7-seg display.
thanks guys for your help and guidance :)
brennerh: yes, I managed to initialise the RTC, read the date/time and display the time to the 7-seg display.
thanks guys for your help and guidance :)
Please be positive and constructive with your questions and comments.