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Topic: Library for many 7, 14 & 16 segment serial displays (Read 7553 times) previous topic - next topic

A minor upgrade of the library.



This display was already support, I have added some constants for handling the dual color leds and updated the documentation to include it.


Manual and download

Paul__B

Well, I received three of these:

But I could not seem to do anything with it using your library.

Any suggestions?

They are not 7-segment displays  ;)

My orders for them has not arrived yet, it may be a month or two more before I have them and have implemented them (I can, of course, not guarantee I will get them to work with the library).

Paul__B

They are not 7-segment displays
Well, 7, 14, near enough, what's the difference?  :smiley-lol:

This chip seems to be abominably supported.  I could not find anything useful in the Adafruit library.

OK, I'm patient ...  :smiley-cool:   (I waited nearly 3 weeks for the displays, didn't I?)

But they look so cool!

noiasca

#34
Jul 21, 2019, 01:55 pm Last Edit: Jul 21, 2019, 02:00 pm by noiasca
Well, I received three of these
But I could not seem to do anything with it using your library.

Any suggestions?
nice ones. Which chip is used? I only read I2C

Edit: HT16K33 according the pictures ...
have you tried https://www.adafruit.com/product/1427 already?
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nice ones. Which chip is used? I only read I2C

Edit: HT16K33 according the pictures ...
My guess was the HT16K33, this means I will not have any problems with the protocol, but only some work with supporting variable sized digits (8 or 16 bits) and define the numbers and letters for this type of display. None of it difficult, just some work to do.

Paul__B

Edit: HT16K33 according the pictures ...
have you tried https://www.adafruit.com/product/1427 already?
Yes, it is the HT16K33; I did manage to figure that out.

Adafruit makes that breakout and has a library for it, but it seems to be specifically configured for their matrix display rather than the "starburst" displays.

#37
Jul 30, 2019, 01:29 pm Last Edit: Jul 30, 2019, 01:50 pm by HKJ-lygte
Time for another update, this time with four more displays, most of them only verified, but one required some new code.



A single digit HC595 static display, any number of digits can be connected.



A DIY MAX7219 display with larger digits than the usual MAX7219 module.



A fairly large (0,8") HC595 that needs interrupts (This is a new type).



Small HC595 that needs interrupts.

I have added a function for scrolling text.

I have also started on preparing for 14 segments displays, but I have not received the module yet.


Manual and download

Paul__B

Basically, anything with 74HC595s and less than one chip per digit will need interrupts - or well-written code.  And be pretty lousy in performance (inconsistent brightness).

Perhaps you could post the eBay/ Aliexpress (or groan: Amazon) title for each of these displays; not necessarily to a particular vendor but to enable them to be readily found?

I am inclined to get one or two if trivially cheap just to play with, especially that oversize MAX7219 if it really is large.  Even better if green!  :smiley-lol:

#39
Jul 31, 2019, 09:57 am Last Edit: Jul 31, 2019, 10:00 am by HKJ-lygte
Basically, anything with 74HC595s and less than one chip per digit will need interrupts - or well-written code.  And be pretty lousy in performance (inconsistent brightness).
With interrupt you will usually have stable brightness, except if you have some very slow interrupt routines and that is bad programming anyway.
The problems with interrupt is that you loose a timer and some performance of the processor.

Perhaps you could post the eBay/ Aliexpress (or groan: Amazon) title for each of these displays; not necessarily to a particular vendor but to enable them to be readily found?
I know some of the displays can be a bit hard to find, but the problem is maintaining it if I put it in my manual.


I am inclined to get one or two if trivially cheap just to play with, especially that oversize MAX7219 if it really is large.  Even better if green!  :smiley-lol:
You can get the large MAX7219 in any color:
https://www.ebay.com/itm/MAX7219-8-Digit-0-56-7-segment-LED-Module-kit-arduino-AVR-numbers-C-cathode/121031909296

I got the single digit HC595 here:
https://www.ebay.com/itm/0-56-74HC595-1-bit-Red-Digital-Tube-Digit-LED-Display-Module-5v-for-AVR-Arduino/322389569620

The large HC595:
https://www.ebay.com/itm/0-8-7-Segment-4-Bit-Digital-Tube-LED-Display-Module-For-Arduino/401588004429

Paul__B

With interrupt you will usually have stable brightness, except if you have some very slow interrupt routines and that is bad programming anyway.
With properly written and not too busy code using millis(), it should be equally stable.  My particular concern was the problem using HC chips as digit drivers, so the segment brightness will depend on how many segments lit - "8" being substantially dimmer then "1".

I know some of the displays can be a bit hard to find, but the problem is maintaining it if I put it in my manual.
Which is why I suggested the title rather than the link - since it is commonly shared by many "personalities" as they come and go with the otherwise same details.  :smiley-lol:

You can get the large MAX7219 in any color:
https://www.ebay.com/itm/MAX7219-8-Digit-0-56-7-segment-LED-Module-kit-arduino-AVR-numbers-C-cathode/121031909296
Even though there is no selector for colour in that listing.  And for the price, I would expect excellent service!  :smiley-eek:

I got the single digit HC595 here:
https://www.ebay.com/itm/0-56-74HC595-1-bit-Red-Digital-Tube-Digit-LED-Display-Module-5v-for-AVR-Arduino/322389569620
Functional if expensive.  Properly documented.

The large HC595:
https://www.ebay.com/itm/0-8-7-Segment-4-Bit-Digital-Tube-LED-Display-Module-For-Arduino/401588004429
Nasty piece of work, almost as bad as in the other thread.  Completely missing the segment resistors.

With properly written and not too busy code using millis(), it should be equally stable.  My particular concern was the problem using HC chips as digit drivers, so the segment brightness will depend on how many segments lit - "8" being substantially dimmer then "1".
In the loop there will often be stuff that takes time, I always prefer interrupts for scanning displays. With my library it is very easy to do on mega processors.
I believe most, if not all, HC595 scanning/interrupt drivers is without proper resistors and has problems with brightness changes depending on used segments.

Which is why I suggested the title rather than the link - since it is commonly shared by many "personalities" as they come and go with the otherwise same details.  :smiley-lol:
I may try this.

Even though there is no selector for colour in that listing.  And for the price, I would expect excellent service!  :smiley-eek:
In the listing there is a link to "See full item description" where he explains that you must write the color in a comment to your order (Not my preferred way).


Nasty piece of work, almost as bad as in the other thread.  Completely missing the segment resistors.
No surprise.

noiasca

thanks for the 7219 link
(but why do they add unsoldered SMD components to a DIL package, wtf ...  )
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(but why do they add unsoldered SMD components to a DIL package, wtf ...  )
With only 3 resistors/capacitors it is not that hard and I got a spare for each type included.
It is important to solder the SMD parts first!

noiasca

#44
Jul 31, 2019, 02:34 pm Last Edit: Jul 31, 2019, 02:34 pm by noiasca
OT: noiasca is to old for that kind of size ;-). will order more of the green pcb modules as long as they are available...
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