16F84 oscillation strangeness

[bonxer]

I've just started trying to get a PIC 16F84 to work. I bought a programmer, the PIC, some oscillators, and components. I went through a tutorial to make an LED blink, and couldn't figure out why it wasn't working. Turns out it was running too slow. I have a 4 MHz crystal connected, and have delays set to try to make the blink visible. After decreasing the delays, I can see it change once every 8 seconds or so. After removing the delay completely, it blinks a few times per second. So I set up port B to output to a 7 segment display, and can clearly see it cycle through all digits 0 through 9 within a second.

After looking at the post right below concerning appropriate crystals, I noticed that all the ones I bought were series crystals. So I suppose that is part of the problem. The thing that grabbed my attention, though, is that when I went to switch crystals, I did not power off the circuit. I just yanked the crystal out. The PIC continued to operate and display numbers at the same rate, with only 22pF caps on the osc pins connecting to ground. I also noticed that if I remove the caps and just stick a wire in to the osc1 pin, it will run as long as I am touching it.

So my questions are:
A. Is there a way to get a PIC chip to run properly with my series crystals, or should I just throw them in my toolbox and look for parallel ones?

B. Why was the PIC even able to operate in the first place with only a capacitor or wire/finger on OSC1, with no resistor or crystal or anything else?

 

[bmcculla]

For you first question: I think most microcontrollers are designed to work with a parallel crystal. You're probably better of just using one of those.

For your second question: All the wireing in you house emits a 60Hz (or 50Hz depending on where you live) signal. Your body of the wire acts like an antenna coupling this signal into the controller - might be enough to make it work but its operation will be really unpredictable and strange.