Digital clock problem

[deniah]

I made this clock but it have one mistake. Problem is that every single led that is currently on, have shadow wich is shifted eight times backwards. For example if 26-th second led is turned on, there is 18-th led also turned on but with aprox. 20% intensity. This is present in whole system.

On the picture you can see leds that have to be on: 10,20,30,39 and leds that must not be on: 2,12,22,31.

Here is schematic of the clock. I can send source too but comments are on serbian and I must translate it first.

 

[VSMVDD]

maybe its the code

the circuit looks aok...

you could wire a frame update to all the !sclr pins
this way adding a blanking pulse

would rule out the led drivers and setup
and also a mute clock feature in hardware

ha maybe you need pullups enabled or not on port b?? just an after thought

 

[gidimiz]

Hi,

Check out the buffer that you are using and see if you have any leackage voltage. i.e see the when you puls 0V from the PIC, you get 0 at the buffer and also at its output. Myaby you are geeting voltage from other pines or something. Dont forget that you are using Transistors ( link the 2003 buff ) that will output voltage relative to the input, and not gust 1 or 0.
Maybe you can find schmit trigger buffer with the same pinout as the 2003, and then you can be sure that they will be only on or only off.

I would start with the voltage on the pines, from the PIC up to the LED with simple voltmeter.

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Good luck.