lcd stops after about 5 minutes and gets stuck

[robertpeach]

thanks for the help!

made a difference, although i still had a problem. in the end i tried putting a capacitor (about 470micro ohms) across the input voltage and the ground. this made my pic work real smooth and now all my programs run completely fine over long periods of time!

unfortunately im not an expert on schematics of electronics and it was probably quite obvious to a seasoned programmer... can anyone explain the physical reason behind why this worked? sorry im quite interested in knowing this kind of stuff.

[mackrackit]

Properly sized caps near the PIC across VDD/VSS will help do a final clean up of the power. The power supply may have nice clean power but a lot can happen along the way to the PIC.

Larger caps most anyplace in the circuit will help with short "brown outs" a short term battery of sorts.

That is all the technical I feel like today . But it should give you the idea.

[Archangel]

thanks for the help!

made a difference, although i still had a problem. in the end i tried putting a capacitor (about 470micro ohms) across the input voltage and the ground. this made my pic work real smooth and now all my programs run completely fine over long periods of time!

unfortunately im not an expert on schematics of electronics and it was probably quite obvious to a seasoned programmer... can anyone explain the physical reason behind why this worked? sorry im quite interested in knowing this kind of stuff.

I have found putting a .01 µF capacitor on the lcd power pins helps too

[dias11]

Thanks everyone. i put

@ DEVICE pic16F877 ' System Device
@ DEVICE pic16F877, WDT_ON ' Watchdog Timer
@ DEVICE pic16F877, PWRT_ON ' Power-On Timer
@ DEVICE pic16F877, BOD_ON ' Brown-Out Detect
@ DEVICE pic16F877, LVP_OFF ' Low-Voltage Programming
@ DEVICE pic16F877, CPD_OFF ' Data Memory Code Protect
@ DEVICE pic16F877, PROTECT_OFF ' Program Code Protection
@ DEVICE pic16F877, XT_OSC


and all works fine.

[robertpeach]

thanks mack and joe.s

yeah that makes total sense, i was just being a bit idiotic i think! it just stores energy almost and then when there is a fluctuation in power source, the capacitor releases the built up charge to oppose the change.

[mackrackit]

thanks mack and joe.s

yeah that makes total sense, i was just being a bit idiotic i think! it just stores energy almost and then when there is a fluctuation in power source, the capacitor releases the built up charge to oppose the change.

That was a good question. Not idiotic.

Oppose the change. Yes, we must.