Scrolling thermo

[pedja089]

Maybe pull up resistor is missing?

[gadelhas]

Hi;

In PIC16F628A the RA4 Pin is open drain, so you wll need a pull up resistor.

[fratello]

Working soft in simulation !!!

[fratello]

Mr.Arrati say : " PortA.4 is a Schmitt Trigger input and an open drain output. You will need an additional NPN transistor with a pull down resistor to make column 5 working.". So... can I use PortA.5 instead PortA.4 ? How ? Using "MCLR off" and ?!

[gadelhas]

Mr.Arrati say : " PortA.4 is a Schmitt Trigger input and an open drain output. You will need an additional NPN transistor with a pull down resistor to make column 5 working.". So... can I use PortA.5 instead PortA.4 ? How ? Using "MCLR off" and ?!

You can only use RA5 as Input with MCLR off

[fratello]

This is schematic who work fine in Proteus. In "real life" , despite modification of scroll timming (pause 500 to 5000 !), the led's are always ON !!! Any idea ?
Thanks !

[gadelhas]

Hi;

I cannot compile that source code. What is the "LOOP" for?? This is a reserved word, you cannot compile the code with this word on a label. And i'm always getting illegal opcode.

What are you using to compile? Mpasm? or PBP?

[gadelhas]

Got it;
Since I'm using MPASM needed to change the config line;

@ __config _INTOSC_OSC_NOCLKOUT & _WDT_OFF & _PWRTE_OFF & _BODEN_OFF & _MCLRE_ON

Also like i said before needed to delete the "LOOP" label also, since its a reserved word.

[mister_e]

This is schematic who work fine in Proteus. In "real life" , despite modification of scroll timming (pause 500 to 5000 !), the led's are always ON !!! Any idea ?
Thanks !

Are they FULL ON or dimmed? I feel they will be dimmed, it's a kind of ghost probably you'll need to add some delay after you turn them off, after the PORTB=0 line

Turn some LED ON, wait a little bit, turn them OFF, wait a little, do it again.

[fratello]

I will try this code today, later...

....
LOOPing:
FOR scroll = 0 TO 35
    FOR scan = 0 TO 15
        PORTb = 1
        porta=1
        FOR counter = 0 TO 7
            PORTA = leddata [counter]
            PAUSE 10
            PORTb = PORTb * 2
        NEXT
    NEXT
    FOR counter = 0 TO 34
        leddata [counter] = leddata [counter+1]
    NEXT
NEXT
GOTO START
END

I find another ...mistake (?) : line 2 do not appear on matrix ! What a hell it's going ?!