a couple reletively simple questions

[k7michal]

even though I've been programming in PIC assembly for about a year now there are two little things I still don't quite understand.

1. what are "weak pull-up resistors" used for? Really, I've never come across a moment where I felt I needed them. Most of my projects involve LED displays and buttons.

2. What is the WDT for. I've read the description in the PIc texts several times, but once again I feel I've never had to use it.

everybody's time is most appreciated.

 

[motion]

1. what are "weak pull-up resistors" used for? Really, I've never come across a moment where I felt I needed them. Most of my projects involve LED displays and buttons.

If they are enabled, these keep unused (open) input line at a know state (high). If you have been reading other posts here, you would see the problems with open input lines.

2. What is the WDT for. I've read the description in the PIc texts several times, but once again I feel I've never had to use it.

The watch dog timer is a device that keeps watch at the operation of the microcontroller. The WDT resets the microcontroller should it hang because of any hardware or software problem. If the WDT enabled, the software should periodically reset the timer before it expires or else the WDT will reset the micro.