I'm trying to reset a PIC18 by a direct connection from MCLR to ground, but cannot get it to work. Circuit attached. The MCLR pin is enabled.

 

Sorry but your "schematic" sounds strange to me.

C1? C2? Would you mind drawing that part by hand?

 

Did you set the MCLR enable bit in the config word? I have no idea what value your R1 is...Is it close to 10K? Are you indeed using the QFN package part?...Different packages have different MCLR pin numbers.

 

Did you set the MCLR enable bit in the config word? I have no idea what value your R1 is...Is it close to 10K? Are you indeed using the QFN package part?...Different packages have different MCLR pin numbers.

Sorry.. forgot to indicate values. 10k resistor and 100NF cap. Yes, the MCLR enable bit is on. It is QFN.

 

What are you using to program the PIC?
Are there any error/warning messages when compiling/assembling or programming your code?
Post the complete project code.

 

Sorry but your "schematic" sounds strange to me.

C1? C2? Would you mind drawing that part by hand?

Thanks for not replying my post.

 

A search this morning of the Microchip site for the 18LF2520 returned:



Clicking on documents gives the same message. Are you absolutely sure that is the correct device?

How are you programming it (i.e., low voltage or high voltage?).

 

It's been out for a while; Digi-Key carries it. But he should have stated the part in the post instead of relying on us reading the poorly drawn circuit diagram.

 

Thanks for the help guys. After a long night I tested another chip and it worked fine. The first chip was defective.

My apologies if I didn't post things correctly. I thought I gave the pertinent details but apparently I didn't. I'm an amateur with electronics and forums as well.

Thanks...

 

It is possible to overload MCLR in reset. That is why Microchip gives a recommended circuit with a series resistor. In my experience, it is extremely rare to get a chip from the manufacturer that is defective. That is, I have never had that experience.