I'm using a Atmega32u4 in standalone mode. Chip is soldered to a PCB with a 16Mhz xtal and I've programmed the Sparkfun Caterina-promicro16.hex bootloader.
I previously tried the Caterina-Leonardo.hex from Arduino but when I upload sketches I have to keep resetting the processor before the upload would start (very tricky timing and a pain when writing / debugging code with lots of uploads)
It seems I don't have this issue with the Sparkfun version.
Programming bootloader:
avrdude -c usbtiny -p m32u4 -U flash:w:Caterina-promicro16.hex
The Sparkfun bootloader uploads fine. I then plug the device in the PC and can see it on USB:
[371282.346575] usb 6-2: new full-speed USB device number 20 using uhci_hcd
[371282.760661] usb 6-2: New USB device found, idVendor=1b4f, idProduct=9205, bcdDevice= 0.01
[371282.760664] usb 6-2: New USB device strings: Mfr=2, Product=1, SerialNumber=0
[371282.760666] usb 6-2: Product: Pro Micro 5V
[371282.760668] usb 6-2: Manufacturer: SparkFun Electronics
The problem I'm having now is when I upload a sketch using Arduino IDE 1.8.13 (Same issue with PlatformIO) is the sketch uploads fine but the bootloader is also overwritten and I"m back to the reset problem.
After upload of the sketch and replugging into USB:
[371521.089317] usb 6-2: New USB device found, idVendor=2341, idProduct=8036, bcdDevice= 1.00
[371521.089320] usb 6-2: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[371521.089322] usb 6-2: Product: Arduino Leonardo
[371521.089324] usb 6-2: Manufacturer: Arduino LLC
How can I stop the bootloader from being overwritten and keep the Sparkfun bootloader?
Debug of the upload on Arduino if it helps:
Sketch uses 6118 bytes (21%) of program storage space. Maximum is 28672 bytes.
Global variables use 485 bytes (18%) of dynamic memory, leaving 2075 bytes for local variables. Maximum is 2560 bytes.
Forcing reset using 1200bps open/close on port /dev/ttyACM0
PORTS {/dev/ttyACM0, /dev/ttyS0, } / {/dev/ttyACM0, /dev/ttyS0, } => {}
PORTS {/dev/ttyACM0, /dev/ttyS0, } / {/dev/ttyACM0, /dev/ttyS0, } => {}
PORTS {/dev/ttyACM0, /dev/ttyS0, } / {/dev/ttyACM0, /dev/ttyS0, } => {}
PORTS {/dev/ttyACM0, /dev/ttyS0, } / {/dev/ttyACM0, /dev/ttyS0, } => {}
PORTS {/dev/ttyACM0, /dev/ttyS0, } / {/dev/ttyACM0, /dev/ttyS0, } => {}
PORTS {/dev/ttyACM0, /dev/ttyS0, } / {/dev/ttyACM0, /dev/ttyS0, } => {}
PORTS {/dev/ttyACM0, /dev/ttyS0, } / {/dev/ttyACM0, /dev/ttyS0, } => {}
PORTS {/dev/ttyACM0, /dev/ttyS0, } / {/dev/ttyACM0, /dev/ttyS0, } => {}
PORTS {/dev/ttyACM0, /dev/ttyS0, } / {/dev/ttyACM0, /dev/ttyS0, } => {}
PORTS {/dev/ttyACM0, /dev/ttyS0, } / {/dev/ttyACM0, /dev/ttyS0, } => {}
PORTS {/dev/ttyACM0, /dev/ttyS0, } / {/dev/ttyACM0, /dev/ttyS0, } => {}
PORTS {/dev/ttyACM0, /dev/ttyS0, } / {/dev/ttyACM0, /dev/ttyS0, } => {}
PORTS {/dev/ttyACM0, /dev/ttyS0, } / {/dev/ttyACM0, /dev/ttyS0, } => {}
PORTS {/dev/ttyACM0, /dev/ttyS0, } / {/dev/ttyACM0, /dev/ttyS0, } => {}
PORTS {/dev/ttyACM0, /dev/ttyS0, } / {/dev/ttyACM0, /dev/ttyS0, } => {}
PORTS {/dev/ttyACM0, /dev/ttyS0, } / {/dev/ttyACM0, /dev/ttyS0, } => {}
PORTS {/dev/ttyACM0, /dev/ttyS0, } / {/dev/ttyACM0, /dev/ttyS0, } => {}
PORTS {/dev/ttyACM0, /dev/ttyS0, } / {/dev/ttyACM0, /dev/ttyS0, } => {}
PORTS {/dev/ttyACM0, /dev/ttyS0, } / {/dev/ttyACM0, /dev/ttyS0, } => {}
PORTS {/dev/ttyACM0, /dev/ttyS0, } / {/dev/ttyACM0, /dev/ttyS0, } => {}
Uploading using selected port: /dev/ttyACM0
/home/greg/.arduino15/packages/arduino/tools/avrdude/6.3.0-arduino17/bin/avrdude -C/home/greg/.arduino15/packages/arduino/tools/avrdude/6.3.0-arduino17/etc/avrdude.conf -v -patmega32u4 -cavr109 -P/dev/ttyACM0 -b57600 -D -Uflash:w:/tmp/arduino_build_198866/i2c_scanner.ino.hex:i
avrdude: Version 6.3-20190619
Copyright (c) 2000-2005 Brian Dean, http://www.bdmicro.com/
Copyright (c) 2007-2014 Joerg Wunsch
System wide configuration file is "/home/greg/.arduino15/packages/arduino/tools/avrdude/6.3.0-arduino17/etc/avrdude.conf"
User configuration file is "/home/greg/.avrduderc"
User configuration file does not exist or is not a regular file, skipping
Using Port : /dev/ttyACM0
Using Programmer : avr109
Overriding Baud Rate : 57600
AVR Part : ATmega32U4
Chip Erase delay : 9000 us
PAGEL : PD7
BS2 : PA0
RESET disposition : dedicated
RETRY pulse : SCK
serial program mode : yes
parallel program mode : yes
Timeout : 200
StabDelay : 100
CmdexeDelay : 25
SyncLoops : 32
ByteDelay : 0
PollIndex : 3
PollValue : 0x53
Memory Detail :
Block Poll Page Polled
Memory Type Mode Delay Size Indx Paged Size Size #Pages MinW MaxW ReadBack
----------- ---- ----- ----- ---- ------ ------ ---- ------ ----- ----- ---------
eeprom 65 20 4 0 no 1024 4 0 9000 9000 0x00 0x00
flash 65 6 128 0 yes 32768 128 256 4500 4500 0x00 0x00
lfuse 0 0 0 0 no 1 0 0 9000 9000 0x00 0x00
hfuse 0 0 0 0 no 1 0 0 9000 9000 0x00 0x00
efuse 0 0 0 0 no 1 0 0 9000 9000 0x00 0x00
lock 0 0 0 0 no 1 0 0 9000 9000 0x00 0x00
calibration 0 0 0 0 no 1 0 0 0 0 0x00 0x00
signature 0 0 0 0 no 3 0 0 0 0 0x00 0x00
Programmer Type : butterfly
Description : Atmel AppNote AVR109 Boot Loader
Connecting to programmer: .
Found programmer: Id = "CATERIN"; type = S
Software Version = 1.0; No Hardware Version given.
Programmer supports auto addr increment.
Programmer supports buffered memory access with buffersize=128 bytes.
Programmer supports the following devices:
Device code: 0x44
avrdude: devcode selected: 0x44
avrdude: AVR device initialized and ready to accept instructions
Reading | ################################################## | 100% 0.00s
avrdude: Device signature = 0x1e9587 (probably m32u4)
avrdude: reading input file "/tmp/arduino_build_198866/i2c_scanner.ino.hex"
avrdude: writing flash (6118 bytes):
Writing | ################################################## | 100% 0.53s
avrdude: 6118 bytes of flash written
avrdude: verifying flash memory against /tmp/arduino_build_198866/i2c_scanner.ino.hex:
avrdude: load data flash data from input file /tmp/arduino_build_198866/i2c_scanner.ino.hex:
avrdude: input file /tmp/arduino_build_198866/i2c_scanner.ino.hex contains 6118 bytes
avrdude: reading on-chip flash data:
Reading | ################################################## | 100% 0.10s
avrdude: verifying ...
avrdude: 6118 bytes of flash verified
avrdude done. Thank you.
