Big 7 seg LED display

[Zhao Hui]

shahidali55 and all you guys in this forum......... thank's alot for technical information my job almost done now...
once again thaaaaankkkkkkkkk's

pic 16F628 with 4digits (10 inc) 7seg 12 Volt



zhao hui

[Zhao Hui]

Here the final Schem that work fine, no software modification on PIC ..... just use the CMOS Inverter (4049 - Hex Inverter) to invert the logic.

[shahidali55]

I'm having certain 'strange' errors in my digital clock.
Processor = 16F84A @ 4 Mhz
4 inch , 12 volt LED Display
The schematic is almost the same as the one in the previous post.
(A battery backup has been added)

Problem 1:-
The clock sometimes just 'hangs'. I think the oscillator stops or something.
The display goes blank or most of the time only one digit on . . .

Problem 2:-
Timer0 is used for timekeeping (Darrel Taylor's Instant Interrupts).
The clock suddenly stops incrementing time.
i.e. the display multiplex routine keeps working as it can be seen that the all the digits on the display are displaying time.
The thing is that the time never increments.
I have programmed the colon between the digits to blink at 0.5 Hz.
This blinking is controller by the time keeping registers mid byte which is kept updated by timer0.
Since the digits keep showing a frozen time, and the colon stops blinking,
Could it be that timer0 has somehow accidentally been disabled ? ? ?


Attached Files :-

clock.pbp - main file
TMR0_int(ASM).pbp - interrupt handler

Could someone please help me out ?