Atmega32U4

[hughkojack]

Hi Peter,

Can I use this bootloader on Atmega32U4 micro controller? it is connected to MCP2515 and TJA1050T as can transceiver.

Thanks

[crycode-de]

Hi, I've added support for the ATmega32U4 mcu according to the datasheet.
Should be working, but can't test it cause of missing hardware.

I've also released v2.2.2 of the flash app with support for the ATmega32U4.

Can yout test it and give me some feedback if it's working?

[hughkojack]

Sure, I will test it and will let you know.
Thanks

[hughkojack]

Hi Peter,
I couldn't upload a new bootloader still, I have an issue with platformio.ini configuration.
this is my new configuration for ATMEGA32U4, can you please see what is wrong.

; PlatformIO Project Configuration File
;
;   Build options: build flags, source filter
;   Upload options: custom upload port, speed and extra flags
;   Library options: dependencies, extra library storages
;   Advanced options: extra scripting
;
; Please visit documentation for the other options and examples
; https://docs.platformio.org/page/projectconf.html

[platformio]
default_envs = ATmega32U4

[env]
platform = atmelavr
framework = arduino

build_flags = 
	-Os
	-funsigned-char
	-funsigned-bitfields
	-fpack-struct
	-fshort-enums
	-fno-exceptions
	-fno-jump-tables
	-mrelax
	-Wl,--relax
	-Wl,--cref
	-Wl,-Map=$BUILD_DIR/firmware.map

board_build.f_cpu = 16000000L

upload_protocol = costom
upload_flags =
    -C
    ; use "tool-avrdude-megaavr" for the atmelmegaavr platform
    ${platformio.packages_dir}/tool-avrdude/avrdude.conf
    -p
    $BOARD_MCU
    -P
    $UPLOAD_PORT
    -c
    usbasp
upload_command = avrdude $UPLOAD_FLAGS -U flash:w:$SOURCE:i

upload_port = COM7
upload_speed = 19200

[env:ATmega32]
board = leonardo
build_flags = 
	${env.build_flags}
	-Wl,--section-start=.text=0x7000

[env:ATmega32U4]
board = leonardo
board_build.mcu = atmega32u4
build_flags = 
	${env.build_flags}
	-Wl,--section-start=.text=0x7000 ; 2048 words bootloader, 0x3800 * 2

board_fuses.lfuse = 0xDE
board_fuses.hfuse = 0x98
board_fuses.efuse = 0xFB

[env:ATmega328P]
board = ATmega328P
build_flags = 
	${env.build_flags}
	-Wl,--section-start=.text=0x7000

[env:ATmega64]
board = ATmega64
build_flags = 
	${env.build_flags}
	-Wl,--section-start=.text=0xF000

[env:ATmega644P]
board = ATmega644P
build_flags = 
	${env.build_flags}
	-Wl,--section-start=.text=0xF000

[env:ATmega128]
board = ATmega128
build_flags = 
	${env.build_flags}
	-Wl,--section-start=.text=0x01F000

[env:ATmega1284P]
board = ATmega1284P
build_flags = 
	${env.build_flags}
	-Wl,--section-start=.text=0x01F000

[env:ATmega2560]
board = ATmega2560
build_flags = 
	${env.build_flags}
	-Wl,--section-start=.text=0x03F000

;board_fuses.lfuse = 0xFF
;board_fuses.hfuse = 0xDA
;board_fuses.efuse = 0xFC

; ***
; Additional environments as examples below
; ***

; ATmega328P with AVR ISP MK2
[env:ATmega328P_via_AVRISP_mkII]
board = ATmega328P
build_flags = 
	${env.build_flags}
	-Wl,--section-start=.text=0x7000

board_build.f_cpu = 16000000L

board_fuses.lfuse = 0xFF
board_fuses.hfuse = 0xD8
board_fuses.efuse = 0xFC

upload_protocol = custom
upload_port = usb
upload_flags = 
	-C
	${platformio.packages_dir}/tool-avrdude/avrdude.conf
	-p
	$BOARD_MCU
	-P
	$UPLOAD_PORT
	-c
	stk500v2
upload_command = avrdude $UPLOAD_FLAGS -U flash:w:$SOURCE:i

[hughkojack]

I am using USBasp programmer which works fine with Arduino IDE.
this is the error I receive and couldn't resolve it.

Processing ATmega32U4 (board: leonardo; platform: atmelavr; framework: arduino)
------------------------------------------------------------------------------------------------------------------------------------------------------
Verbose mode can be enabled via `-v, --verbose` option
CONFIGURATION: https://docs.platformio.org/page/boards/atmelavr/leonardo.html
PLATFORM: Atmel AVR (4.1.0) > Arduino Leonardo
HARDWARE: ATMEGA32U4 16MHz, 2.50KB RAM, 28KB Flash
DEBUG: Current (simavr) External (simavr)
PACKAGES:
 - framework-arduino-avr @ 5.1.0
 - toolchain-atmelavr @ 1.70300.191015 (7.3.0)
LDF: Library Dependency Finder -> https://bit.ly/configure-pio-ldf
LDF Modes: Finder ~ chain, Compatibility ~ soft
Found 5 compatible libraries
Scanning dependencies...
No dependencies
Building in release mode

Selected fuses: [lfuse = 0xFF, hfuse = 0xD8, efuse = 0xCB]
Setting fuses
avrdude: ser_open(): can't open device "\\.\COM7": The system cannot find the file specified.

[crycode-de]

Seams like avrdude can't find your selected port COM7.
Have checked that this is the correct port? Windows sometimes likes to assign new port numbers.

Also

upload_protocol = costom

should be

upload_protocol = custom

😉

Additional remark:
One the fuses are set, you should comment out the board_fuses.* lines to not set the fuses again on each flash.

[hughkojack]

Thanks for your comment, the usb port was not correct.

[hughkojack]

after uploading the new bootloader the USB of Atmega32U4 is not responding

[crycode-de]

Don't know what exactly you mean and I've no personal experience with the ATmega32U4 so far.

But if it's something like programming via USB ... this will most likely work via a bootloader which handles the USB communication.
If you flashed the mcp-can-boot bootloader, you have overwritten the original bootloader.
There can only be one bootloader at a time. 😉

[hughkojack]

how did you find these numbers

#elif defined(AVR_ATmega32U4)
#define IV_REG MCUCR

#define SPI_DDR DDRB
#define SPI_PORT PORTB
#define SPI_SS 0
#define SPI_MOSI 2
#define SPI_MISO 3
#define SPI_SCK 1

as per pinout shouldn't be as following:
#define SPI_SS 17
#define SPI_MOSI 16
#define SPI_MISO 14
#define SPI_SCK 15

[crycode-de]

from the datasheet of the ATmega32U4

Pinout on page 3 or chapter "10.3.1 Alternate Functions of Port B" on page 74.

Your pin numbers 14..17 looks like Arduino pin numbers. The bootloader uses the real pin numbers of the controller.

[hughkojack]

it seems that I'm not able to identify the exact location where the bootloader is getting stuck. I can observe that the LED is flashing with a period of approximately 1000ms, indicating that the bootloader is running. However, for some reason, the main sketch is not starting.

[crycode-de]

Seams like the bootloader is starting but the main application is missing, so the controller restarts every time the bootloader tries to start the main application.
Did you flash your application after flashing the bootloader?