Pololu USB AVR - Manual (Page 34)

Serial Number
This is a unique identifier assigned to this programmer by Pololu. This number can not be changed.
TTL Serial Port
This section is used to identify pins A and B with serial handshaking lines so that they can be used as general purpose
user I/O lines. See
Section 6.a .
AVR ISP Emulation
This section is used to change the hardware and software version numbers of the programmer. These numbers are
read by Atmel Studio when it connects to the programmer and are expressed in hex. If these numbers do not match
the numbers that Atmel Studio expects, then it might bring up a dialog asking if you want to upgrade (or downgrade)
your programmer’s firmware; the Pololu AVR USB programmer does not support this method of firmware upgrading,
so this dialog is nothing more than a nuisance to those not using an Atmel programmer. You should click Cancel to
ignore the message and proceed to the AVRISP programming dialog. To prevent this firmware-upgrade dialog from
appearing in the future, set the numbers here to the numbers that AVR Studio says it expects.
Pololu USB AVR Programmer User's Guide © 2001–2014 Pololu Corporation
3. Getting Started in Windows Page 34 of 54