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LDmicro Forum - ladder for 4 digit 7 segment LED display (multiplexed)

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ladder for 4 digit 7 segment LED display (multiplexed) (by jayakumar)
Thank you very much

any one can help me howto creat ladder for 4 digit 7 segment
LED display connected at pin no 21 to 27 of pic16f876A.
Tue Dec 22 2009, 06:33:41
no subject (by simon)
Hi jayakumar. I use this program with mega32 . U need to extract only wath is important to you .
I hope is wath you need .
Tue Dec 22 2009, 09:13:09, download attachment ceas32.zip
(no subject) (by Joao Pereira)
Hi, One off the examples in the donwload sector is exactly what you need.
Tue Dec 22 2009, 16:25:46
(no subject) (by S A Khan)
Thank you Simon
Wed Dec 23 2009, 07:24:29
7segment display 4 digit multiplex in ldmicro (by khalid)
Send me please ldmicro projects examples
Mon Feb 1 2016, 13:22:27
(no subject) (by Tom J.)
I modified one of Jonathan's ladders to test a common anode 4 digit display and automated it to count up. This version also removes the 0 place holder on digits that aren't being used.
Wed Oct 24 2018, 01:03:46, download attachment 7seg2.ld
(no subject) (by Tom J.)
Here's a tricky one:
I'm using multiplexed common anode displays. The PIC has all the anodes with 1k resistors to limit the current, no transistors.
Does anyone have a ladder to use adc input to do dimming by varying the timing on the anodes or a simple hardware solution?
My project has many s and displays so simple or software would be great.
Thanks in advance, Tom
Sat Oct 27 2018, 21:48:01
(no subject) (by MGP)
Use the PWM (0..1000) output with the ADC value and switch the common anode or common cathode.
Sun Oct 28 2018, 05:21:26
(no subject) (by Tom J.)
I'm not certain that would work with the arrangement of the anodes.
The PIC16F886 I'm working with does have multiple PWM outputs but I don't think I can use them as general IO at the same time.

Sun Oct 28 2018, 15:08:20
(no subject) (by MGP)
Then use a software pwm.
The program attached is not mine, I found it on this forum.

Use a fast cycletime and it is not necessary to count to 100, counting to 10 also works.

Play with it..
Mon Oct 29 2018, 03:40:32, download attachment Software-PWM.ld
(no subject) (by Tom J.)
I tried implementing the software PWM several ways and between the cycling of the commons and the PWM all it does is blink at different rates.
I think I'm just going to use a PWM and some transistors to divide some power away from the common anodes.
It was an elegant solution, at least I tried.
Tue Nov 13 2018, 00:44:48
(no subject) (by MGP)
Why do you need pwm on a display?

Btw.In this thread I posted a better version of your display program, a version without reflections in the digits.

Tue Nov 13 2018, 03:35:46
(no subject) (by Tom J.)
I'm having a lot of fun with LDMicro and decided to write a set of digital gauges for the next car I'm gearing up to build. I need to dim the displays so it's not overpowering at night and since I'm having fun I figured PWM would be interesting to learn and then the scale can be set in the ladder rather than changing electronics later if I decide to revise it.

The Odometer was first, now I'm almost done with the clock and I only have two more to write since the speedo and tach are similar in function and temp, oil press, fuel level and misc others are essentially the same with a little different scale for each.

Starting with the clock gives me a project where I can learn how to use the 7 segment driver and figure out things like dimming.

I've got the cycle time at 2.0 with Johnathan's 7 Segment driver and it looks pretty goodas far as shadow characters. That 7 segment driver you wrote is a little less complex, I'll have to play with it a bit.
I'm running PIC16F886 and so far I'm only hitting about 23% of it's capacity but I'm always up for more simplicity.

Thank you for your help again MGP.
Tue Nov 13 2018, 16:19:52
readin an seria input (by Rogério Francisco)
Help, i need to read a serial input
Sat Nov 17 2018, 13:48:16
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