HOLTEK HT16K33 Driving 7 Seven segment

[jay_dee]

Hi,
There is a existing component for the Holtek HT16K33. It is for driving grid arrays of LEDs
but it can be used with Seven Segment displays.

If anyone else want to achieve this using the existing component this may help.

Rows - These drive the individual segments.
Columns - These select which segmented digit is being driven.

NOTE:
It would appear single bits are used to drive each segment of a digit and each segment value will be 1,2,4,8,16,32,64 or 128
For example I found the top bar to be a value of 2 (bit1) and the bottom bar to be a value of 16 (bit4)

I also found Column value 0 was for the left most digit
Column 2 for the next digit
Column 4 was for the center ":"
Column 6 was for the 3rd digit.
Column 8 was for the last digit.

These Values may vary between modules and how they are wired.
SO you may need to re-work this using this first bit of FC.

The first FC has two loops, ONLY enable one at a time.
The first loop steps through the individual segment values so you can note the segments and thus determine the associated Bit values.
Add up all the required values and it gets you a single Value to enable the correct pattern of segments for your digit.
For example for a Display of '1' I noted had bit values of 4 & 8 for the two right Bars, thus a display character of '1' requires a value of 4+8 = 12.

The first FC also has a second loop, if you run this it cycles through an array holding the pattern/character values that were found to work with the ADAFRUIT i2C 7 segment displays.

HT16K33_Digit_Test.fcfx

(26.77 KiB) Downloaded 20 times

The second FC
this takes an Integer value, breaks it into individual number Charaters 123 = 1,2,3
Then writes these to the correct columns. Again, it was correct for my columns but you experiance may be different.

HT16K33_Value_Test.fcfx

(36.18 KiB) Downloaded 17 times

This FC may be a bit clunky but it seem to works and may help get you started. J.