How do does the logic analyzer in the Pic Kit 2 work?

Thread Starter

spinnaker

Joined Oct 29, 2009
7,830
I own a Pic Kit 2 and not a 3. I understand there is a logic analyzer in the Pic Kit 2.

I was watching this video

http://www.eevblog.com/2009/10/21/eevblog-39-pickit-3-programmerdebugger-review/

(which is hilarious BTW, especially the response)

and noticed the 2 does not seem to have any extra wires for the analyzer.

How does it work then? Is it just the registers that are being read and the pins not actually sampled?
 

JohnInTX

Joined Jun 26, 2012
4,787
It works by reconfiguring the 2 ISCP + 1 Aux lines as logic inputs when the logic tool application is running.

Details in the Logic Tool User's Guide

While they say its useful for viewing SPI/I2C I would caution that that is so only when you are certain that the bus is clean as the slow sample rate would leave much unseen.
 
Last edited:

Markd77

Joined Sep 7, 2009
2,806
It just uses the pins on the PICKIT that would normally be used for data, clock and the spare pin. It's not very high speed, but has come in handy a couple of times.
 

Thread Starter

spinnaker

Joined Oct 29, 2009
7,830
I see, so the lines are re-purposed. Thanks guys.

Does the serial input work the same way?

I wonder why no one has come up with a hack to add the logic analyzer back to the Pic Kit 3? Or is the boot loader proprietary for the 3? Or could you even get the original firmware to replace it back?
 
Top