.\"
.\" avrdude - A Downloader/Uploader for AVR device programmers
.\" Copyright (C) 2001, 2002, 2003  Joerg Wunsch
.\"
.\" This program is free software; you can redistribute it and/or modify
.\" it under the terms of the GNU General Public License as published by
.\" the Free Software Foundation; either version 2 of the License, or
.\" (at your option) any later version.
.\"
.\" This program is distributed in the hope that it will be useful,
.\" but WITHOUT ANY WARRANTY; without even the implied warranty of
.\" MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
.\" GNU General Public License for more details.
.\"
.\" You should have received a copy of the GNU General Public License
.\" along with this program; if not, write to the Free Software
.\" Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
.\"
.\"
.\" $Id$
.\"
.Dd DATE July 24, 2003
.Os
.Dt AVRDUDE 1
.Sh NAME
.Nm avrdude
.Nd driver program for ``simple'' Atmel AVR MCU programmer
.Sh SYNOPSIS
.Nm
.Fl p Ar partno
.Op Fl c Ar programmer-id
.Op Fl C Ar config-file
.Op Fl e
.Oo Fl E Ar exitspec Ns
.Op \&, Ns Ar exitspec
.Oc
.Op Fl f Ar format
.Op Fl F
.Op Fl i Ar filename
.Op Fl m Ar memtype
.Op Fl o Ar filename
.Op Fl n
.Op Fl P Ar port
.Op Fl t
.Op Fl v
.Op Fl V
.Op Fl y
.Op Fl Y
.Sh DESCRIPTION
.Nm Avrdude
is a program for downloading code and data to Atmel AVR
microcontrollers.
.Nm Avrdude
supports Atmel's STK500 programmer as well as a simple hard-wired
programmer connected directly to a
.Xr ppi 4
parallel port.  In the simplest case, the hardware consists just of a
cable connecting the respective AVR signal lines to the parallel port.
.Pp
The MCU is programmed in
.Em serial programming mode ,
so, for the
.Xr ppi 4
based programmer, the MCU signals
.Ql /RESET ,
.Ql SCK ,
.Ql MISO
and
.Ql MOSI
need to be connected to the parallel port.  Optionally, some otherwise
unused output pins of the parallel port can be used to supply power
for the MCU part, so it is also possible to construct a passive
standalone programming device.  Some status LEDs indicating the
current operating state of the programmer can be connected, and a
signal is available to control a buffer/driver IC 74LS367 (or
74HCT367).  The latter can be useful to decouple the parallel port
from the MCU when in-system programming is used.
.Pp
See the file
.Pa ${PREFIX}/share/doc/avrdude/avrdude.pdf
for a schematic of the
.Xr ppi 4
based programming hardware.
.Pp
Atmel's STK500 programmer is also supported and connects to a serial
port.
.Pp
Input files can be provided, and output files can be written in
different file formats, such as raw binary files containing the data
to download to the chip, Intel hex format, or Motorola S-record
format.  There are a number of tools available to produce those files,
like
.Xr asl 1
as a standalone assembler, or
.Xr avr-objcopy 1
for the final stage of the GNU toolchain for the AVR microcontroller.
.Pp
.Nm Avrdude
can program the EEPROM and flash ROM memory cells of supported AVR
parts.  Where supported by the serial instruction set, fuse bits and
lock bits can be programmed as well.  These are implemented within
.Nm
as seperate memory types and can be programmed using data from a file
(see the
.Fl m
option) or from terminal mode (see the
.Ar dump
and
.Ar write
commands).  It is also possible to read the chip (provided it has not
been code-protected previously, of course) and store the data in a
file.  Finally, a ``terminal'' mode is available that allows one to
interactively communicate with the MCU, and to display or program
individual memory cells.
On the STK500 programmer, several operational parameters (target supply
voltage, target Aref voltage, master clock) can be examined and changed
from within terminal mode as well.
.Ss Options
In order to control all the different operation modi, a number of options
need to be specified to
.Nm avrdude .
.Bl -tag -offset indent -width indent
.It Fl p Ar partno
This is the only option that is mandatory for every invocation of
.Nm avrdude .
It specifies the type of the MCU connected to the programmer.  These are read from the config file.  If
.Nm avrdude
does not know about a part that you have, simply add it to the config
file (be sure and submit a patch back to the author so that it can be
incorporated for the next version).  See the sample config file for
the format.  Currently, the following MCU types are understood:
.Pp
.TS
ll.
\fBOption tag\fP	\fBOfficial part name\fP
t15	ATtiny15
1200	AT90S1200
2313	AT90S2313
2333	AT90S2333
2343	AT90S2343 (*)
4414	AT90S4414
4433	AT90S4433
4434	AT90S4434
8515	AT90S8515
8535	AT90S8535
m163	ATMEGA163
m169	ATMEGA169
m128	ATMEGA128
m103	ATMEGA103
m16	ATMEGA16
m8	ATMEGA8
.TE
.Bl -tag -width "(*) "
.It "(*)"
The AT90S2323 uses the same algorithm.
.El
.It Fl c Ar programmer-id
Use the pin configuration specified by the argument.  Pin
configurations are read from the config file (see the
.Fl C
option).  New pin configurations can be easily added or modified
through the use of a config file to make
.Nm avrdude
work with different programmers as long as the programmer supports the
Atmel AVR serial program method.  You can use the 'default_programmer'
keyword in your
.Pa ${HOME}/.avrduderc
file to assign a default programmer to keep from having to specify
this option on every invocation.
.It Fl C Ar config-file
Use the specified config file to load configuration data.  This file
contains all programmer and part definitions that
.Nm avrdude
knows about.  If you have a programmer or part that
.Nm avrdude
does not know about, you can add it to the config file (be sure and
submit a patch back to the author so that it can be incorporated for
the next version).  See the config file, located at
.Pa ${PREFIX}/etc/avrdude.conf ,
which contains a description of the format.
.It Fl e
Causes a chip erase to be executed.  This will reset the contents of the
flash ROM and EEPROM to the value
.Ql 0xff ,
and is basically a prerequisite command before the flash ROM can be
reprogrammed again.  The only exception would be if the new
contents would exclusively cause bits to be programmed from the value
.Ql 1
to
.Ql 0 .
Note that in order to reprogram EERPOM cells, no explicit prior chip
erase is required since the MCU provides an auto-erase cycle in that
case before programming the cell.
.It Xo Fl E Ar exitspec Ns
.Op \&, Ns Ar exitspec
.Xc
By default,
.Nm
leaves the parallel port in the same state at exit as it has been
found at startup.  This option modifies the state of the
.Ql /RESET
and
.Ql Vcc
lines the parallel port is left at, according to the
.Ar exitspec
arguments provided, as follows:
.Bl -tag -width noreset
.It Ar reset
The
.Ql /RESET
signal will be left activated at program exit, that is it will be held
.Em low ,
in order to keep the MCU in reset state afterwards.  Note in particular
that the programming algorithm for the AT90S1200 device mandates that
the
.Ql /RESET
signal is active
.Em before
powering up the MCU, so in case an external power supply is used for this
MCU type, a previous invocation of
.Nm
with this option specified is one of the possible ways to guarantee this
condition.
.It Ar noreset
The
.Ql /RESET
line will be deactivated at program exit, thus allowing the MCU target
program to run while the programming hardware remains connected.
.It Ar vcc
This option will leave those parallel port pins active
.Pq \&i. \&e. Em high
that can be used to supply
.Ql Vcc
power to the MCU.
.It Ar novcc
This option will pull the
.Ql Vcc
pins of the parallel port down at program exit.
.El
.Pp
Multiple
.Ar exitspec
arguments can be separated with commas.
.It Fl f Ar format
This option specifies the file format for the input or output files
to be processed.
.Ar Format
can be one of:
.Bl -tag -width sss
.It Ar i
Intel Hex
.It Ar s
Motorola S-record
.It Ar r
raw binary; little-endian byte order, in the case of the flash ROM data
.It Ar m
immediate; actual byte values specified on the command line, seperated
by commas or spaces.  This is good for programming fuse bytes without
having to create a single-byte file or enter terminal mode.
.It Ar a
auto detect; valid for input only, and only if the input is not
provided at
.Em stdin .
.El
.Pp
The default is to use auto detection for input files, and raw binary
format for output files.
.It Fl F
Normally,
.Nm
tries to verify that the device signature read from the part is
reasonable before continuing.  Since it can happen from time to time
that a device has a broken (erased or overwritten) device signature
but is otherwise operating normally, this options is provided to
override the check.
.It Fl i Ar filename
Specifies the input file to be programmed into the MCU.  Can be specified
as
.Ql \&-
to use
.Em stdin
as the input.
.It Fl I Ar data
Same as specifying
.Fl i
and
.Fl f Ar m
together, i.e., this is a shortcut for using immediate file input mode
where the filename field is used as the data itself.  Useful for
programming single byte memories such as fuse bytes without having to
use single byte files or enter interactive terminal mode.
.It Fl m Ar memtype
Specifies which program area of the MCU to read or write; allowable
values depend on the MCU being programmed, but most support at least
.Em eeprom
for the EEPROM, and
.Em flash
for the flash ROM.  Use the
.Fl v
option on the command line or the
.Ar part
command from terminal mode to display all the memory types supported
by a particular device.  The default is
.Em flash .
.It Fl n
No-write - disables actually writing data to the MCU (useful for debugging
.Nm avrdude
).
.It Fl o Ar filename
Specifies the name of the output file to write, and causes the respective
memory area to be read from the MCU.  Can be specified as
.Ql \&-
to write to
.Em stdout .
.It Fl P Ar port
Use
.Ar port
to identify the device to which the programmer is attached.  By
default the
.Pa /dev/ppi0
port is used, but if the programmer type normally connects to the
serial port, the
.Pa /dev/cuaa0
port is the default.  If you need to use a different parallel or
serial port, use this option to specify the alternate port name.
.It Fl t
Tells
.Nm
to enter the interactive ``terminal'' mode instead of up- or downloading
files.  See below for a detailed description of the terminal mode.
.It Fl v
Enable verbose output.
.It Fl V
Disable automatic verify check when uploading data.
.It Fl y
Tells
.Nm
to use the last four bytes of the connected parts' EEPROM memory to
track the number of times the device has been erased.  When this
option is used and the
.Fl e
flag is specified to generate a chip erase, the previous counter will
be saved before the chip erase, it is then incremented, and written
back after the erase cycle completes.  Presumably, the device would
only be erased just before being programmed, and thus, this can be
utilized to give an indication of how many erase-rewrite cycles the
part has undergone.  Since the FLASH memory can only endure a finite
number of erase-rewrite cycles, one can use this option to track when
a part is nearing the limit.  The typical limit for Atmel AVR FLASH is
1000 cycles.  Of course, if the application needs the last four bytes
of EEPROM memory, this option should not be used.
.It Fl Y Ar cycles
Instructs
.Nm
to initialize the erase-rewrite cycle counter residing at the last four
bytes of EEPROM memory to the specified value.  If the application
needs the last four bytes of EEPROM memory, this option should not be
used.
.El
.Ss Terminal mode
In this mode,
.Nm
only initializes communication with the MCU, and then awaits user
commands on standard input.  Commands and parameters may be
abbreviated to the shortest unambiguous form.  Terminal mode provides
a command history using
.Xr readline 3 ,
so previously entered command lines can be recalled and edited.  The
following commands are currently implemented:
.Bl -tag -offset indent -width indent
.It Ar dump memtype addr nbytes
Read
.Ar nbytes
bytes from the specified memory area, and display them in the usual
hexadecimal and ASCII form.
.It Ar dump
Continue dumping the memory contents for another
.Ar nbytes
where the previous
.Ar dump
command left off.
.It Ar write memtype addr byte1 ... byteN
Manually program the respective memory cells, starting at address
.Ar addr ,
using the values
.Ar byte1
through
.Ar byteN .
This feature is not implemented for bank-addressed memories such as
the flash memory of ATMega devices.
.It Ar erase
Perform a chip erase.
.It Ar send b1 b2 b3 b4
Send raw instruction codes to the AVR device.  If you need access to a
feature of an AVR part that is not directly supported by
.Nm ,
this command allows you to use it, even though
.Nm
does not implement the command.
.It Ar sig
Display the device signature bytes.
.It Ar part
Display the current part settings.
.It Ar vtarg voltage
Set the target's supply voltage to
.Ar voltage
Volts.
.Em Only supported on the STK500 programmer.
.It Ar varef voltage
Set the adjustable voltage source to
.Ar voltage
Volts.
This voltage is normally used to drive the target's
.Em Aref
input on the STK500.
.Em Only supported on the STK500 programmer.
.It Ar fosc freq Ns Op M Ns \&| Ns k
Set the master oscillator to
.Ar freq
Hz.
An optional trailing letter
.Ar \&M
multiplies by 1E6, a trailing letter
.Ar \&k
by 1E3.
.Em Only supported on the STK500 programmer.
.It Ar fosc off
Turn the master oscillator off.
.Em Only supported on the STK500 programmer.
.It Ar parms
Display the current voltage and master oscillator parameters.
.Em Only supported on the STK500 programmer.
.It Ar \&?
.It Ar help
Give a short on-line summary of the available commands.
.It Ar quit
Leave terminal mode and thus
.Nm avrdude .
.El
.Ss Default Parallel port pin connections
(these can be changed, see the
.Fl c
option)
.TS
ll.
\fBPin number\fP	\fBFunction\fP
2-5	Vcc (optional power supply to MCU)
7	/RESET (to MCU)
8	SCK (to MCU)
9	MOSI (to MCU)
10	MISO (from MCU)
18-25	GND
.TE
.Sh FILES
.Bl -tag -offset indent -width /dev/ppi0XXX
.It Pa /dev/ppi0
default device to be used for communication with the programming
hardware
.It Pa ${PREFIX}/etc/avrdude.conf
programmer and parts configuration file
.It Pa ${HOME}/.avrduderc
programmer and parts configuration file (per-user overrides)
.It Pa ~/.inputrc
Initialization file for the
.Xr readline 3
library
.It Pa ${PREFIX}/share/doc/avrdude/avrdude.pdf
Schematic of programming hardware
.El
.\" .Sh EXAMPLES
.\" .Sh DIAGNOSTICS
.Sh SEE ALSO
.Xr avr-objcopy 1 ,
.Xr ppi 4 ,
.Xr readline 3
.Pp
The AVR microcontroller product description can be found at
.Pp
.Dl "http://www.atmel.com/products/AVR/"
.\" .Sh HISTORY
.Sh AUTHORS
.Nm Avrdude
was written by Brian S. Dean <bsd@bsdhome.com>.
.Pp
This man page by
.ie t J\(:org Wunsch.
.el Joerg Wunsch.
.Sh BUGS
Please report bugs to avrdude-dev@nongnu.org.