bonus-features

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.)