I2C based seven segment display

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Joined Jun 10, 2022
In this task you are required to display time on a I2C based seven segment display. The time should at 00:00 (minutes, seconds) when the microcontroller is started and internal timing should be used to keep the time. You may use millis function for this purpose. In the simulator you should be using HT16K33 Backback 7-segment display. This device has multiple commands to control its behaviour and a system to setup output of the device. To initiate the device, you must send following commands either in a single transmission or one by one to the device: • 0x21: Turn on clock • 0xE?: Set brightness ? should be replaced by the brightness value. Use 0xEF for full brightness. • 0x81: Enable display In order to update the display, you should first send the starting section. The controller supports up to 16 sections each having 16 segments in it. However, in our device we have 5 section, first and last two have 8 segment digits (7-segments + .), middle section :) sign) only has 1 segment at bit 1. After sending the starting section, without ending the transmission, send 2 bytes per section (2nd bytes do not matter as each section is 8 bits) to set their state. This will allow you to control segments on each 7-segment display. Once the data is written, end the transmission to request device to apply your changes. If you want to change all sections at once, you need to send 0 and then 10 bytes to set the state of each section. Draw your circuit and write your program on this page. Use the back of the paper if necessary.


Joined Apr 2, 2020

The jumpers (semi-circle pads) on the lower left are used to set the I2C address of the Holtek chip you reference.

Google: Adafruit 7-segment backpack I2C
Then look for the Arduino library and code to do what is needed. Your initialization process is executed by the library with a begin statement for the graphics object. Read through and let me know if you can't figure it out. There is plenty of adafruit example code out there for these backpacks.