7580173593
Previously, the code would limit the clock to 1Mhz. If a higher clock
was specified, it would be set to 1.024Mhz (0x400 khz).
This commit removes this artificial limit, while still preventing
overflowing the two bytes available in the command (effectively limiting
to 65535 kHz).
The original limit seems inappropriate, because the JTAGEICE3 and ATMEL
ICE actually support higher clocks than the old limit. For SPI, the
JTAGICE3 documents supporting up to 1.875Mhz and the ATMEL ICE up to
5Mhz. In practice the JTAGEICE3 (with the newer EDBG version where it
becomes pretty much identical to the ATMEL ICE) also works up to 5Mhz.
When trying to set higher values, the behaviour seems to depend on the
current value. The programmer seems to either keep the previous value
(e.g. from 3Mhz to 10Mhz), or use 8kHz / 125μs (e.g. from 5Mhz to
10Mhz). In any case, the value read back afterwards (and printed with
-v) reflects the actual value.
Also note that the code also applies a lower limit of 1kHz (to ensure
the raw value sent to the device, in kHz, is never zero), but in
practice sending a value of lower than 8kHz ends up setting 8kHz
(125μs). This is also the minimum value in the device documentation.
This commit was tested with:
Programmer Type : JTAG3_ISP
Description : Atmel AVR JTAGICE3 in ISP mode
ICE HW version : 2
ICE FW version : 3.55 (rel. 130)
AVRDUDE
AVRDUDE - AVR Downloader Uploader - is a program for downloading and uploading the on-chip memories of Microchip’s AVR microcontrollers. It can program the Flash and EEPROM, and where supported by the programming protocol, it can program fuse and lock bits. AVRDUDE also supplies a direct instruction mode allowing one to issue any programming instruction to the AVR chip regardless of whether AVRDUDE implements that specific feature of a particular chip.
AVRDUDE was originally written in 2003 by Brian S. Dean. Since 2006, AVRDUDE has been maintained by Jörg Wunsch, with the help of various contributors.
The latest version of AVRDUDE is always available here:
https://github.com/avrdudes/avrdude
Documentation
Documentation for current and previous releases is on Github Pages.
Getting AVRDUDE for Windows
To get AVRDUDE for Windows, install the latest version from the Releases page.
Alternatively, you may build AVRDUDE yourself from source.
Getting AVRDUDE for Linux
To install AVRDUDE for Linux, install the package avrdude using the software package manager. For example, under Debian/Ubuntu, you can use the following commands:
sudo apt-get install avrdude
Alternatively, you may build AVRDUDE yourself from source.
Getting AVRDUDE for macOS
On macOS, AVRDUDE can be installed through MacPorts or Homebrew.
Alternatively, you may build AVRDUDE yourself from source.
Using AVRDUDE
AVRDUDE is a command-line application. Run the command avrdude without any arguments for a list of options.
A typical command to program your HEX file into your AVR microcontroller looks like this:
avrdude -c <programmer> -p <part> -U flash:w:<file>:i
For instance, to program an Arduino Uno connected to the serial port COM1 with a HEX file called blink.hex,
you would run the following command:
avrdude -c arduino -P COM1 -b 115200 -p atmega328p -D -U flash:w:objs/blink.hex:i
There are many different programmers and options that may be required for the programming to succeed.
For more information, refer to the AVRDUDE documentation.