The Pololu USB AVR Programmer is an extremely compact, low-cost in-system programmer (ISP) for Atmel’s AVR mirocontrollers, which makes this device an attractive programming solution for AVR-based controllers like Pololu Orangutan robot controllers. The USB AVR programmer connects to your computer’s USB port via an included USB A to mini-B cable and communicates with your programming software, such as AVR Studio or AVRDUDE, through a virtual COM port using the AVRISPV2/STK500 protocol. The programmer connects to your target device via an included 6-pin ISP programming cable (the older, 10-pin ISP connections are not directly supported, but it’s easy to create or purchase a 6-pin-to-10-pin ISP adapter).

Supported Microcontrollers

The programmer should work with all AVRs that can be programmed by an AVR ISP, but it has not been tested on all devices (it has been tested with all Orangutan robot controllers and the 3pi Robot). The programmer features upgradable firmware, allowing updates for future devices. It does not currently work with Atmel’s XMega line of microcontrollers.

The programmer is powered by the 5V USB power bus, and it is intended for programming AVRs that are running at close to 5 V (note that the programmer does not deliver power to the target device). You can use it to program AVRs running at lower voltages if you use voltage dividers to decrease the voltage of the programmer’s output pins to a level that is safe for your microcontroller.

Supported Operating Systems

The programmer has been tested under Windows XP, Windows Vista, and Linux. It is not compatible with any version of Mac OS or with older versions of Windows. Please see our original Orangutan USB programmer if you need something that can work with the Mac OS (we don’t support Mac operation, but other users have used it successfully) or older versions of Windows.

Bonus Feature: TTL-level serial port

Like our original Orangutan USB programmer, the USB AVR programmer doubles as a USB-to-serial adapter, but with a few key improvements. The programmer installs as two virtual COM ports: one for communicating with programming software and one for the general-purpose USB-to-serial adapter. This means that you can seamlessly switch between programming an AVR and debugging it through the TTL serial port without having to open and close your terminal program. In addition to the serial transmit (TX), and receive (RX), lines, the programmer lets you use pins A and B as serial handshaking lines. The programmer’s configuration utility allows you to select which handshaking line is assigned to which pin, and both input and output handshaking lines are supported. The programmer also gives you access to the USB’s regulated 5V power bus through the VBUS pin.

Bonus Feature: SLO-scope

This device can also act as a two-channel, severely limited oscilloscope (SLO-scope) using the A and B pins as analog voltage inputs and the Pololu SLO-scope application for Windows. The SLO-scope can measure voltages between 0 and ~5 V (the maximum is limited by the USB bus voltage), or higher if you use an external voltage divider, and it supports two sampling modes: 10 kHz sampling of two 8-bit analog inputs or 20 kHz sampling of one 7-bit analog input and one digital input. This feature can help you debug your circuits and firmware by seeing what the voltages are doing at various nodes. (Please note that the SLO-scope feedback is quite limited and is not intended as a substitute for a real oscilloscope or a good multimeter, which will have much higher input impedance, better resolution and range, and higher sampling frequency.)

Included Accessories

The Pololu USB AVR Programmer ships with a 12" (30 cm) 6-pin ISP programming cable and a 6’ (1.8 m) USB A to mini-B cable. It does not ship with software or documentation, but software (including drivers) and documentation can be found under the resources tab.

Pololu USB AVR programmer with included six-pin ISP cable and USB A to mini-B cable.

Pololu USB AVR Programmer User’s Guide (Printable PDF: pololu_usb_avr_programmer.pdf)

The complete guide to using the Pololu USB AVR programmer. This guide covers programming AVR microcontrollers, communicating via the USB-to-TTL-serial adapter, and measuring voltages using the SLO-scope.