serial receive pin and
RX
is an input that connects to your target’s serial transmit pin.
describes how to use these lines to communicate with your devices from the
computer.
The
A
and
B
lines can be used as serial control/handshaking lines for the USB-to-TTL-serial
adapter (see
) or as analog voltage inputs for the SLO-scope (see
).
Pololu USB AVR programmer bottom view with dimensions.
The USB AVR programmer has a standard
6-pin AVR ISP connector
for programming
AVRs, and the pins are labeled on the silkscreen on the bottom side of the board. The pins
on the connector are:
1.
MISO
: The “Master Input, Slave Output” line for SPI communication with the target
AVR. The programmer is the master, so this line is an input.
2.
VDD
: An input line that the programmer uses to measure the voltage of the target
AVR. While programming the target device, the programmer uses this line to constantly
monitor the target VDD. If the voltage goes too low or varies too much, then the
programmer aborts programming in order to avoid damage to the target AVR.
has more information about target VDD monitoring. The VDD line is not used to
power the programmer; the programmer is powered from the USB. This line cannot be
used to power the target device; the target device must be independently powered for
programming to work.
3.
SCK
: The clock line for SPI communication with the target AVR. The programmer is
the master, so this line is an output during programming.
4.
MOSI
: The “Master Output, Slave Input” line for SPI communication with the target
AVR. The programmer is the master, so this line is an output during programming.
5.
RST
: The target AVR’s reset line. This line is used as an output driven low during
programming to hold the AVR in reset.
6.
GND
: Ground. This line should be connected to the target device’s ground.
1.b. Supported Microcontrollers
The Pololu USB AVR 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
[http://www.pololu.com/catalog/category/8]
and
the
[http://www.pololu.com/catalog/product/975]
). The programmer features upgradable
firmware, allowing updates for future devices. It does not currently work with Atmel’s line
of XMega microcontrollers.
Pololu USB AVR Programmer User's Guide
© 2001–2010 Pololu Corporation
1. Overview
Page 4 of 36
