user16842: there is AVR AVR ATmega32 and a board within. 
there is outputs for all ports (A, B, C, D) on board, and Vcc. 
the problem is - I have no external GND output.
to watch current - I should search for GND pin everytime. 
and now I need ground on my solderless board for LEDs and temperature sensor. 
let's guess that I have no idea what is current or electricity.
so the question is: where I can find ground to connect it to solderless board?
maybe I can use something else, except MCU? (like my hand or smth :D)


user10794: Pin 11 of the chip itself is GND (see below). In the photo it appears to have a decoupling capacitor between GND and VCC (pin 10). You could solder a wire onto pin 11 (on the chip socket, not the pin itself) - it might be easier on the back of the board. Also pin 31 would be an option.


Also the reset switch is almost certainly wired (on one side) to GND. It looks to me like most of the board is "ground plane" (continuous copper) so find which part of the switch is wired to that, and solder a wire to it.

user16842: I've just sorted things out.
There is two interfaces - ISP and JTAG. ISP is busy with programmer everytime, but JTAG is free.
So, I have found pinout of JTAG interface and achieved GND.
There is pinout:

(source: digital-circuitry.com)

16842: <p>there is AVR AVR ATmega32 and a board within. 
there is outputs for all ports (A, B, C, D) on board, and Vcc. 
the problem is - I have no external GND output.
to watch current - I should search for GND pin everytime. 
and now I need ground on my solderless board for LEDs and temperature sensor. </p>

<p>let's guess that I have no idea what is current or electricity.
so the question is: where I can find ground to connect it to solderless board?
maybe I can use something else, except MCU? (like my hand or smth :D)
<img src="https://pp.vk.me/c627928/v627928177/35713/n4HlnXV5PTo.jpg" alt="board photo"></p>
 10794: <p>Pin 11 of the chip itself is GND (see below). In the photo it appears to have a decoupling capacitor between GND and VCC (pin 10). You could solder a wire onto pin 11 (on the chip socket, not the pin itself) - it might be easier on the back of the board. Also pin 31 would be an option.</p>

<p><a href="https://i.stack.imgur.com/Wadpv.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/Wadpv.png" alt="Atmega32 pinouts"></a></p>

<hr>

<p>Also the reset switch is almost certainly wired (on one side) to GND. It looks to me like most of the board is "ground plane" (continuous copper) so find which part of the switch is wired to that, and solder a wire to it.</p>
 16842: <p>I've just sorted things out.<br />
There is two interfaces - ISP and JTAG. ISP is busy with programmer everytime, but JTAG is free.<br />
So, I have found pinout of JTAG interface and achieved GND.<br />
There is pinout:
<a href="https://i.stack.imgur.com/l1oe6.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/l1oe6.jpg" alt="isp-and-jtag" /></a><br />
<sub>(source: <a href="http://www.digital-circuitry.com/IMAGES/webpage/MyLAB/Altera/JTAG_ISP.jpg" rel="nofollow noreferrer">digital-circuitry.com</a>)</sub></p>
