Chip45boot-free AVR bootloader

Topics:

Why this bootloader is different? This is based on standard Motorola s-record compatible file which can be easily generated from Intel HEX. Firmware can be transferred via standard UART of any AVR microcontroller. File can be transferred using any Hyper terminal program or your own program. Just note, that it is necessary to have a delay of 250ms after each line transmitted. This can be set with almost all Hyper terminal program.

Download process can be automatized by using command line tool, which can be called from Makefile or another application.

Bootloader is programmed in C using WINAVR toolset version 20060421. There is Programmers notepad project file included in package. If you decide to adapt bootloader to another MCU then adjust MCU_NAME and bootloader flash page address in the makefile. There is few predefined definitions included (Atmega8, Atmega128, Atmega168). If you add new microcontrollers you will have to add some new register definitions in mcudefs.h file.

How to use Chip45boot bootloader:

  • Program chip45boot into a mcu.

  • Adjust the fuse bits to activate bootloader functionality.

  • Open a terminal program.

  • Hold key 'i' pressed during power up or reset of the MCU. (a prompt should appear)

  • Press 'f' or 'e' to program flash or EEPROM.

  • Drag and drop the .srec file into the terminal windows (might not work with any terminal program, if not start the upload of a text file through a menu option).

  • After programming, the bootloader starts again.

  • Press 'g' to start the application or reset the MCU.

Simple test program is included in chip45boot.zip file – LED flashing. This program is also written with WINAvr and compatible with Atmega8.

Code size of bootloader is less that 1kbyte.

hip45boot is provided under the terms of the Lesser General Public License (LGPL).

chip45boot s-record bootloader for the Atmel AVR microcontrollers.

chip45prog desktop command line tools for chip45boot.

Source: chip45.com