PIC&74ls47

watzmann said:

Hi All ,

i have built a circuit that connect pic16f84a 74ls47 and a coomn anode seven segmant.

i have a aproblem now that all the inputs of the 74ls47 gives 1.3 volts , i don't why.

for that reason my pic ports that connected to the 74ls47 is also 1.3 volts , even if i removed the pic IC .

i'll load the photo of that schematic and please tell me what's wrong.

thank you

Click to expand...

watzmann said:

so you mean that that is normal , and i have to set up my portb to be as output ?

i did soemthing else i made all the portb to be low but nothing happen , anyway i'll try now to set my port b to be output and tell you

Click to expand...

watzmann said:

now i said in my program to let all portb as outputs ,

but it still indicate 1.3 volts ,

!!!!!

Click to expand...

watzmann said:

no i'cm connecting 3 and 5 to +v , but 4 is floating.

someone in this forum told me to do that before , look at this link

https://www.electro-tech-online.com/threads/is-it-right.34268/?highlight=watzmann

Click to expand...

watzmann said:

i'm using picbasic
---------------
DEVICE=16F84A
XTAL=4
TRISB=%0000000
TRISA=%0000000
HIGH PORTB.0
HIGH PORTA.4
-------------

Click to expand...