Continue to Site

Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

Register Log in

[SOLVED] 16f877a power on problem

Status
Not open for further replies.
the input to 7805 must be at least higher than the input by 1.25 v, if u can maintain that the output is guaranteed to be at 5v or 4.99v. hence the normal configuration will suffice. but I had the same problem once due to bad resonator. does your code run on many interrupt routines. you should be careful with interrupt routines, when translated in to assembly or hex they create a lot of mess.
 
Last edited:

I had the same problem once due to bad resonator.
Click to expand...

what does bad resonator means

does your code run on many interrupt routines. you should be careful with interrupt routines, when translated in to assembly or hex they create a lot of mess.
Click to expand...

no there are not much interrupts what could be the problem with interrupts?
 

The resonator that i was using has a power supply pins(Vcc and ground) and phase shifted signal(clock) outputs pins which were connected to the clock input of the PIC, for some reason the resonator was creating too much noise on the power line.
Interrupts if not properly handled, may execute nested and create erratic program flow.
 

Did you used too many functions or big lookup tables???
Click to expand...

yes there are call functions included

The resonator that i was using has a power supply pins(Vcc and ground) and phase shifted signal(clock) outputs pins which were connected to the clock input of the PIC, for some reason the resonator was creating too much noise on the power line.
Click to expand...

i am using simple crystal oscillator with two legs connected to osc pins of controller
 

More function calls could lead to stack over flow and that can lead to undesirable outputs and as well as not correctly sized variables could crash your program....
Click to expand...

i have check my program in proteus and there seems no such problems
 

i have replaced 15pf with 33pf....initially for few days the problem occured but after that its resolved..
thanks all
 

Status
Not open for further replies.

Similar threads

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Back
Top