Help with 16x2 LCD

Ttelmah · Joined: 11 Mar 2010 Posts: 19541

This may well change with different compiler versions. I don't remember seeing what version he is using?. It's possible that he has a version that doesn't have this on by default.

The current compilers (recent V5), leave the fuses in their 'erased' state, unless you set the fuses, but earlier compilers did in some cases set values to 'default' settings.

IamUche · Joined: 10 Aug 2016 Posts: 17

On the software version i saw

PCWHD Compiler

IDE Version 5.010
PCB Version 5.010
PCM Version 5.010
PCH Version 5.010
PCD Version 5.010

Ttelmah · Joined: 11 Mar 2010 Posts: 19541

The place to look for the compiler version is in the listing file. Just the compiler version matters.

However if it is 5.010, then this has some known issues. Particularly the global interrupt will get disabled in printf routines. This could freeze the code depending on what is being done.

IamUche · Joined: 10 Aug 2016 Posts: 17

Please what should I do now coz I'm kinda stuck with this issue?

Thanks in anticipation.

temtronic · Posted: Tue May 23, 2017 4:44 am

OK.. step one is to get the '1 Hz LED program ' running correctly. Please show us your program and what happens.
Since you're using an 877, do you have both caps on the xtal pins?

If it's really slow.....If using MPLAB, have you compiled in 'debug' mode? If yes, change the build option to 'release', recompile (F10), download PIC and test.

Small steps will ensure success.
Jay

IamUche · Joined: 10 Aug 2016 Posts: 17

@temtronic, i have done a successful run of LED oscillating circuit which I posted the code in the previous page. My code runs just fine but I notice that spikes, partial contact or noises at the power terminals (VSS and VDD) is affects the Microcontroller (PIC16f877a) thereby causing it to go into a kind of freeze or latch.
Anyways I came across this post https://www.ccsinfo.com/forum/viewtopic.php?p=165581

Can a watch dog timer, brownout reset solve my case?

Ttelmah · Joined: 11 Mar 2010 Posts: 19541

Seriously what suppression have you got on the chip?.
The microprocessor needs really good HF response (typically ceramic) capacitors immediately adjacent to it's power pins.
The brownout reset will reset the chip if you get significant droops, not little spikes. Your design needs to be generating a clean environment for the chip to start with. Only after this consider code solutions.
All pins should either be connected to circuitry, or driven as outputs (no pins left floating as undriven inputs).
Circuitry round the chip needs it's own suppression.
I often say to look at something like a PC motherboard. The supply on the board, will typically have dozens of large and small capacitors, but then across the board, every other chip will also have suppression capacitors.
Visible spikes are a sign of a design problem.