# New Olimex AVR-P40 questions

**URL:** <https://community.sparkfun.com/t/new-olimex-avr-p40-questions/1427>\
**Category:** MicroMod\
**Tags:** avr-atmel\
**Created:** [February 21, 2006, 5:20pm UTC](https://community.sparkfun.com/t/new-olimex-avr-p40-questions/1427 "2006-02-21T17:20:53Z")\
**Posts on this page:** 2\
**Page:** 1

<div class="post-metadata">

**Author:** ![hruska](https://avatars.discourse-cdn.com/v4/letter/h/ccd318/32.png) [@hruska](https://community.sparkfun.com/u/hruska)\
**Post date:** [February 21, 2006, 5:20pm UTC](https://community.sparkfun.com/t/new-olimex-avr-p40-questions/1427/1 "2006-02-21T17:20:53Z")

</div>

I just bought an AVR-P40 and apparently it is a little bit newer than the current documentation and schematics on line. The board does not list a revision, but it does say Copyright 2005.

It has a “general purpose button” - what port is this wired to?

It also has a jumper labelled “3.3V” which is defaulted to not connected. What is this for? Is it related to the old docs which say there are two jumpers for AVCC/AGND?

Any help (or pointers to new docs/schematics) would be greatly appreciated.

---

<div class="post-metadata">

**Author:** ![hruska](https://avatars.discourse-cdn.com/v4/letter/h/ccd318/32.png) [@hruska](https://community.sparkfun.com/u/hruska)\
**Post date:** [February 21, 2006, 6:51pm UTC](https://community.sparkfun.com/t/new-olimex-avr-p40-questions/1427/2 "2006-02-21T18:51:34Z")

</div>

I think I answered my own question. The schematics for the USB version of the board show a button on PB4. The 3.3V jumper changes the voltage regulator adjustment to (I assume) output 3.3V.