Midiboy USB not recognized by Mac/Ardunio

Hello, I am unable to use my midiboy, my Mac does not recognize it and I cannot upload sketches. I tried on Big Sir, and a older Mac with Catalina and no luck. I made sure all of the settings are correct in Ardunio IDE. I took the battery out. I had any unit professionally soldered and all of the connections are verified. Its not the cable, I tried another cable, and also using the same cable I tried a Arduino mega board and it is immediately recognized.

“the selected serial port
does not exist or your board is not connected”

The unit does not show up in disk utility, or as a serial port in Ardunio.

I am seeing is the “K” logo when powering on in programming mode and normally.

Are there any step I can take to troubleshoot?

Hi, when using USBasp programmer, the Port can be set to anything - USBasp always finds the right device to work with connected via USB. Try doing “Sketch->Upload” anyway.

Also, please enable verbose output in the Arduino’s preferences dialog, as recommended here: Midiboy Software Setup - Step 3, so any upload errors are printed in the log. If there are any errors after upload, please post them here.

The device, when in bootloader mode, is not supposed to be recognized as a USB serial device.

If this doesn’t work on multiple computers, the most likely issue is some incorrect component placement, bad solder joint, a short somewhere, or damaged traces.

Hello, thanks so much for the reply. Here is the full error when trying to upload the sketch:

Arduino: 1.8.13 (Mac OS X), Board: "Midiboy"

/Applications/Arduino.app/Contents/Java/arduino-builder -dump-prefs -logger=machine -hardware /Applications/Arduino.app/Contents/Java/hardware -hardware /Users/tedpedersen/Library/Arduino15/packages -tools /Applications/Arduino.app/Contents/Java/tools-builder -tools /Applications/Arduino.app/Contents/Java/hardware/tools/avr -tools /Users/tedpedersen/Library/Arduino15/packages -built-in-libraries /Applications/Arduino.app/Contents/Java/libraries -libraries /Users/tedpedersen/Documents/Arduino/libraries -fqbn=Blokas:avr:midiboy -vid-pid=0000_0000 -ide-version=10813 -build-path /var/folders/2j/qfqwpm4s51x183j30gf4x0tw0000gn/T/arduino_build_629528 -warnings=none -build-cache /var/folders/2j/qfqwpm4s51x183j30gf4x0tw0000gn/T/arduino_cache_765248 -prefs=build.warn_data_percentage=75 -prefs=runtime.tools.arduinoOTA.path=/Applications/Arduino.app/Contents/Java/hardware/tools/avr -prefs=runtime.tools.arduinoOTA-1.3.0.path=/Applications/Arduino.app/Contents/Java/hardware/tools/avr -prefs=runtime.tools.avr-gcc.path=/Applications/Arduino.app/Contents/Java/hardware/tools/avr -prefs=runtime.tools.avr-gcc-7.3.0-atmel3.6.1-arduino7.path=/Applications/Arduino.app/Contents/Java/hardware/tools/avr -prefs=runtime.tools.avrdude.path=/Applications/Arduino.app/Contents/Java/hardware/tools/avr -prefs=runtime.tools.avrdude-6.3.0-arduino17.path=/Applications/Arduino.app/Contents/Java/hardware/tools/avr -verbose /Users/tedpedersen/Downloads/midimon/midimon.ino
/Applications/Arduino.app/Contents/Java/arduino-builder -compile -logger=machine -hardware /Applications/Arduino.app/Contents/Java/hardware -hardware /Users/tedpedersen/Library/Arduino15/packages -tools /Applications/Arduino.app/Contents/Java/tools-builder -tools /Applications/Arduino.app/Contents/Java/hardware/tools/avr -tools /Users/tedpedersen/Library/Arduino15/packages -built-in-libraries /Applications/Arduino.app/Contents/Java/libraries -libraries /Users/tedpedersen/Documents/Arduino/libraries -fqbn=Blokas:avr:midiboy -vid-pid=0000_0000 -ide-version=10813 -build-path /var/folders/2j/qfqwpm4s51x183j30gf4x0tw0000gn/T/arduino_build_629528 -warnings=none -build-cache /var/folders/2j/qfqwpm4s51x183j30gf4x0tw0000gn/T/arduino_cache_765248 -prefs=build.warn_data_percentage=75 -prefs=runtime.tools.arduinoOTA.path=/Applications/Arduino.app/Contents/Java/hardware/tools/avr -prefs=runtime.tools.arduinoOTA-1.3.0.path=/Applications/Arduino.app/Contents/Java/hardware/tools/avr -prefs=runtime.tools.avr-gcc.path=/Applications/Arduino.app/Contents/Java/hardware/tools/avr -prefs=runtime.tools.avr-gcc-7.3.0-atmel3.6.1-arduino7.path=/Applications/Arduino.app/Contents/Java/hardware/tools/avr -prefs=runtime.tools.avrdude.path=/Applications/Arduino.app/Contents/Java/hardware/tools/avr -prefs=runtime.tools.avrdude-6.3.0-arduino17.path=/Applications/Arduino.app/Contents/Java/hardware/tools/avr -verbose /Users/tedpedersen/Downloads/midimon/midimon.ino
Using board 'midiboy' from platform in folder: /Users/tedpedersen/Library/Arduino15/packages/Blokas/hardware/avr/1.0.6
Using core 'arduino' from platform in folder: /Applications/Arduino.app/Contents/Java/hardware/arduino/avr
Detecting libraries used...
/Applications/Arduino.app/Contents/Java/hardware/tools/avr/bin/avr-g++ -c -g -Os -w -std=gnu++11 -fno-exceptions -ffunction-sections -fdata-sections -fno-threadsafe-statics -flto -w -x c++ -E -CC -mmcu=atmega328p -DF_CPU=20000000L -DARDUINO=10813 -DARDUINO_AVR_MIDIBOY -DARDUINO_ARCH_AVR -DUSB_CFG_IOPORTNAME=D -DUSB_CFG_DMINUS_BIT=3 -DUSB_CFG_DPLUS_BIT=2 -DUSB_CFG_PULLUP_IOPORTNAME=D -DUSB_CFG_PULLUP_BIT=4 -DMIDIBOY=6 -DUSB_INTR_CFG=EICRA -DUSB_INTR_ENABLE=EIMSK -DUSB_INTR_PENDING=EIFR -DUSB_INTR_ENABLE_BIT=INT1 -DUSB_INTR_PENDING_BIT=INTF1 -DUSB_INTR_VECTOR=INT1_vect "-DUSB_INTR_CFG_SET=(1 << ISC11)" -DUSB_COUNT_SOF=1 -I/Applications/Arduino.app/Contents/Java/hardware/arduino/avr/cores/arduino -I/Users/tedpedersen/Library/Arduino15/packages/Blokas/hardware/avr/1.0.6/variants/Midiboy /var/folders/2j/qfqwpm4s51x183j30gf4x0tw0000gn/T/arduino_build_629528/sketch/midimon.ino.cpp -o /dev/null -DARDUINO_LIB_DISCOVERY_PHASE
Alternatives for Midiboy.h: [Midiboy@1.0.0]
ResolveLibrary(Midiboy.h)
  -> candidates: [Midiboy@1.0.0]
/Applications/Arduino.app/Contents/Java/hardware/tools/avr/bin/avr-g++ -c -g -Os -w -std=gnu++11 -fno-exceptions -ffunction-sections -fdata-sections -fno-threadsafe-statics -flto -w -x c++ -E -CC -mmcu=atmega328p -DF_CPU=20000000L -DARDUINO=10813 -DARDUINO_AVR_MIDIBOY -DARDUINO_ARCH_AVR -DUSB_CFG_IOPORTNAME=D -DUSB_CFG_DMINUS_BIT=3 -DUSB_CFG_DPLUS_BIT=2 -DUSB_CFG_PULLUP_IOPORTNAME=D -DUSB_CFG_PULLUP_BIT=4 -DMIDIBOY=6 -DUSB_INTR_CFG=EICRA -DUSB_INTR_ENABLE=EIMSK -DUSB_INTR_PENDING=EIFR -DUSB_INTR_ENABLE_BIT=INT1 -DUSB_INTR_PENDING_BIT=INTF1 -DUSB_INTR_VECTOR=INT1_vect "-DUSB_INTR_CFG_SET=(1 << ISC11)" -DUSB_COUNT_SOF=1 -I/Applications/Arduino.app/Contents/Java/hardware/arduino/avr/cores/arduino -I/Users/tedpedersen/Library/Arduino15/packages/Blokas/hardware/avr/1.0.6/variants/Midiboy -I/Users/tedpedersen/Library/Arduino15/packages/Blokas/hardware/avr/1.0.6/libraries/Midiboy/src /var/folders/2j/qfqwpm4s51x183j30gf4x0tw0000gn/T/arduino_build_629528/sketch/midimon.ino.cpp -o /dev/null -DARDUINO_LIB_DISCOVERY_PHASE
Alternatives for usbmidi.h: [USBMIDI@1.1.5]
ResolveLibrary(usbmidi.h)
  -> candidates: [USBMIDI@1.1.5]
/Applications/Arduino.app/Contents/Java/hardware/tools/avr/bin/avr-g++ -c -g -Os -w -std=gnu++11 -fno-exceptions -ffunction-sections -fdata-sections -fno-threadsafe-statics -flto -w -x c++ -E -CC -mmcu=atmega328p -DF_CPU=20000000L -DARDUINO=10813 -DARDUINO_AVR_MIDIBOY -DARDUINO_ARCH_AVR -DUSB_CFG_IOPORTNAME=D -DUSB_CFG_DMINUS_BIT=3 -DUSB_CFG_DPLUS_BIT=2 -DUSB_CFG_PULLUP_IOPORTNAME=D -DUSB_CFG_PULLUP_BIT=4 -DMIDIBOY=6 -DUSB_INTR_CFG=EICRA -DUSB_INTR_ENABLE=EIMSK -DUSB_INTR_PENDING=EIFR -DUSB_INTR_ENABLE_BIT=INT1 -DUSB_INTR_PENDING_BIT=INTF1 -DUSB_INTR_VECTOR=INT1_vect "-DUSB_INTR_CFG_SET=(1 << ISC11)" -DUSB_COUNT_SOF=1 -I/Applications/Arduino.app/Contents/Java/hardware/arduino/avr/cores/arduino -I/Users/tedpedersen/Library/Arduino15/packages/Blokas/hardware/avr/1.0.6/variants/Midiboy -I/Users/tedpedersen/Library/Arduino15/packages/Blokas/hardware/avr/1.0.6/libraries/Midiboy/src -I/Users/tedpedersen/Library/Arduino15/packages/Blokas/hardware/avr/1.0.6/libraries/USBMIDI/src /var/folders/2j/qfqwpm4s51x183j30gf4x0tw0000gn/T/arduino_build_629528/sketch/midimon.ino.cpp -o /dev/null -DARDUINO_LIB_DISCOVERY_PHASE
Using cached library dependencies for file: /var/folders/2j/qfqwpm4s51x183j30gf4x0tw0000gn/T/arduino_build_629528/sketch/midimon.cpp
Using cached library dependencies for file: /var/folders/2j/qfqwpm4s51x183j30gf4x0tw0000gn/T/arduino_build_629528/sketch/midimon_event_display_mode.cpp
Using cached library dependencies for file: /var/folders/2j/qfqwpm4s51x183j30gf4x0tw0000gn/T/arduino_build_629528/sketch/midimon_font.c
Using cached library dependencies for file: /var/folders/2j/qfqwpm4s51x183j30gf4x0tw0000gn/T/arduino_build_629528/sketch/midimon_renderer.cpp
Using cached library dependencies for file: /var/folders/2j/qfqwpm4s51x183j30gf4x0tw0000gn/T/arduino_build_629528/sketch/midimon_settings.cpp
Alternatives for EEPROM.h: [EEPROM@2.0]
ResolveLibrary(EEPROM.h)
  -> candidates: [EEPROM@2.0]
Using cached library dependencies for file: /var/folders/2j/qfqwpm4s51x183j30gf4x0tw0000gn/T/arduino_build_629528/sketch/midimon_special_symbols.c
Using cached library dependencies for file: /var/folders/2j/qfqwpm4s51x183j30gf4x0tw0000gn/T/arduino_build_629528/sketch/midimon_utils.cpp
Using cached library dependencies for file: /Users/tedpedersen/Library/Arduino15/packages/Blokas/hardware/avr/1.0.6/libraries/Midiboy/src/Midiboy.cpp
Using cached library dependencies for file: /Users/tedpedersen/Library/Arduino15/packages/Blokas/hardware/avr/1.0.6/libraries/Midiboy/src/MidiboyDIN5MIDI.cpp
Using cached library dependencies for file: /Users/tedpedersen/Library/Arduino15/packages/Blokas/hardware/avr/1.0.6/libraries/Midiboy/src/MidiboyDisplay.cpp
Using cached library dependencies for file: /Users/tedpedersen/Library/Arduino15/packages/Blokas/hardware/avr/1.0.6/libraries/Midiboy/src/MidiboyFonts.cpp
Using cached library dependencies for file: /Users/tedpedersen/Library/Arduino15/packages/Blokas/hardware/avr/1.0.6/libraries/Midiboy/src/MidiboyInput.cpp
Using cached library dependencies for file: /Users/tedpedersen/Library/Arduino15/packages/Blokas/hardware/avr/1.0.6/libraries/Midiboy/src/MidiboyUSBMIDI.cpp
Using cached library dependencies for file: /Users/tedpedersen/Library/Arduino15/packages/Blokas/hardware/avr/1.0.6/libraries/Midiboy/src/SH1106.cpp
Alternatives for SPI.h: [SPI@1.0]
ResolveLibrary(SPI.h)
  -> candidates: [SPI@1.0]
Using cached library dependencies for file: /Users/tedpedersen/Library/Arduino15/packages/Blokas/hardware/avr/1.0.6/libraries/USBMIDI/src/midi_serialization.cpp
Using cached library dependencies for file: /Users/tedpedersen/Library/Arduino15/packages/Blokas/hardware/avr/1.0.6/libraries/USBMIDI/src/usbmidi_pluggableusb.cpp
Using cached library dependencies for file: /Users/tedpedersen/Library/Arduino15/packages/Blokas/hardware/avr/1.0.6/libraries/USBMIDI/src/usbmidi_vusb.cpp
Using cached library dependencies for file: /Users/tedpedersen/Library/Arduino15/packages/Blokas/hardware/avr/1.0.6/libraries/USBMIDI/src/vusb.S
Using cached library dependencies for file: /Users/tedpedersen/Library/Arduino15/packages/Blokas/hardware/avr/1.0.6/libraries/USBMIDI/src/vusb.c
Using cached library dependencies for file: /Applications/Arduino.app/Contents/Java/hardware/arduino/avr/libraries/SPI/src/SPI.cpp
Generating function prototypes...
/Applications/Arduino.app/Contents/Java/hardware/tools/avr/bin/avr-g++ -c -g -Os -w -std=gnu++11 -fno-exceptions -ffunction-sections -fdata-sections -fno-threadsafe-statics -flto -w -x c++ -E -CC -mmcu=atmega328p -DF_CPU=20000000L -DARDUINO=10813 -DARDUINO_AVR_MIDIBOY -DARDUINO_ARCH_AVR -DUSB_CFG_IOPORTNAME=D -DUSB_CFG_DMINUS_BIT=3 -DUSB_CFG_DPLUS_BIT=2 -DUSB_CFG_PULLUP_IOPORTNAME=D -DUSB_CFG_PULLUP_BIT=4 -DMIDIBOY=6 -DUSB_INTR_CFG=EICRA -DUSB_INTR_ENABLE=EIMSK -DUSB_INTR_PENDING=EIFR -DUSB_INTR_ENABLE_BIT=INT1 -DUSB_INTR_PENDING_BIT=INTF1 -DUSB_INTR_VECTOR=INT1_vect "-DUSB_INTR_CFG_SET=(1 << ISC11)" -DUSB_COUNT_SOF=1 -I/Applications/Arduino.app/Contents/Java/hardware/arduino/avr/cores/arduino -I/Users/tedpedersen/Library/Arduino15/packages/Blokas/hardware/avr/1.0.6/variants/Midiboy -I/Users/tedpedersen/Library/Arduino15/packages/Blokas/hardware/avr/1.0.6/libraries/Midiboy/src -I/Users/tedpedersen/Library/Arduino15/packages/Blokas/hardware/avr/1.0.6/libraries/USBMIDI/src -I/Applications/Arduino.app/Contents/Java/hardware/arduino/avr/libraries/EEPROM/src -I/Applications/Arduino.app/Contents/Java/hardware/arduino/avr/libraries/SPI/src /var/folders/2j/qfqwpm4s51x183j30gf4x0tw0000gn/T/arduino_build_629528/sketch/midimon.ino.cpp -o /var/folders/2j/qfqwpm4s51x183j30gf4x0tw0000gn/T/arduino_build_629528/preproc/ctags_target_for_gcc_minus_e.cpp -DARDUINO_LIB_DISCOVERY_PHASE
/Applications/Arduino.app/Contents/Java/tools-builder/ctags/5.8-arduino11/ctags -u --language-force=c++ -f - --c++-kinds=svpf --fields=KSTtzns --line-directives /var/folders/2j/qfqwpm4s51x183j30gf4x0tw0000gn/T/arduino_build_629528/preproc/ctags_target_for_gcc_minus_e.cpp
Compiling sketch...
Using previously compiled file: /var/folders/2j/qfqwpm4s51x183j30gf4x0tw0000gn/T/arduino_build_629528/sketch/midimon_font.c.o
Using previously compiled file: /var/folders/2j/qfqwpm4s51x183j30gf4x0tw0000gn/T/arduino_build_629528/sketch/midimon_special_symbols.c.o
Using previously compiled file: /var/folders/2j/qfqwpm4s51x183j30gf4x0tw0000gn/T/arduino_build_629528/sketch/midimon_utils.cpp.o
Using previously compiled file: /var/folders/2j/qfqwpm4s51x183j30gf4x0tw0000gn/T/arduino_build_629528/sketch/midimon_renderer.cpp.o
/Applications/Arduino.app/Contents/Java/hardware/tools/avr/bin/avr-g++ -c -g -Os -w -std=gnu++11 -fno-exceptions -ffunction-sections -fdata-sections -fno-threadsafe-statics -MMD -flto -mmcu=atmega328p -DF_CPU=20000000L -DARDUINO=10813 -DARDUINO_AVR_MIDIBOY -DARDUINO_ARCH_AVR -DUSB_CFG_IOPORTNAME=D -DUSB_CFG_DMINUS_BIT=3 -DUSB_CFG_DPLUS_BIT=2 -DUSB_CFG_PULLUP_IOPORTNAME=D -DUSB_CFG_PULLUP_BIT=4 -DMIDIBOY=6 -DUSB_INTR_CFG=EICRA -DUSB_INTR_ENABLE=EIMSK -DUSB_INTR_PENDING=EIFR -DUSB_INTR_ENABLE_BIT=INT1 -DUSB_INTR_PENDING_BIT=INTF1 -DUSB_INTR_VECTOR=INT1_vect "-DUSB_INTR_CFG_SET=(1 << ISC11)" -DUSB_COUNT_SOF=1 -I/Applications/Arduino.app/Contents/Java/hardware/arduino/avr/cores/arduino -I/Users/tedpedersen/Library/Arduino15/packages/Blokas/hardware/avr/1.0.6/variants/Midiboy -I/Users/tedpedersen/Library/Arduino15/packages/Blokas/hardware/avr/1.0.6/libraries/Midiboy/src -I/Users/tedpedersen/Library/Arduino15/packages/Blokas/hardware/avr/1.0.6/libraries/USBMIDI/src -I/Applications/Arduino.app/Contents/Java/hardware/arduino/avr/libraries/EEPROM/src -I/Applications/Arduino.app/Contents/Java/hardware/arduino/avr/libraries/SPI/src /var/folders/2j/qfqwpm4s51x183j30gf4x0tw0000gn/T/arduino_build_629528/sketch/midimon.ino.cpp -o /var/folders/2j/qfqwpm4s51x183j30gf4x0tw0000gn/T/arduino_build_629528/sketch/midimon.ino.cpp.o
Using previously compiled file: /var/folders/2j/qfqwpm4s51x183j30gf4x0tw0000gn/T/arduino_build_629528/sketch/midimon_event_display_mode.cpp.o
Using previously compiled file: /var/folders/2j/qfqwpm4s51x183j30gf4x0tw0000gn/T/arduino_build_629528/sketch/midimon.cpp.o
Using previously compiled file: /var/folders/2j/qfqwpm4s51x183j30gf4x0tw0000gn/T/arduino_build_629528/sketch/midimon_settings.cpp.o
Compiling libraries...
Compiling library "Midiboy"
Using previously compiled file: /var/folders/2j/qfqwpm4s51x183j30gf4x0tw0000gn/T/arduino_build_629528/libraries/Midiboy/MidiboyDisplay.cpp.o
Using previously compiled file: /var/folders/2j/qfqwpm4s51x183j30gf4x0tw0000gn/T/arduino_build_629528/libraries/Midiboy/MidiboyFonts.cpp.o
Using previously compiled file: /var/folders/2j/qfqwpm4s51x183j30gf4x0tw0000gn/T/arduino_build_629528/libraries/Midiboy/MidiboyDIN5MIDI.cpp.o
Using previously compiled file: /var/folders/2j/qfqwpm4s51x183j30gf4x0tw0000gn/T/arduino_build_629528/libraries/Midiboy/Midiboy.cpp.o
Using previously compiled file: /var/folders/2j/qfqwpm4s51x183j30gf4x0tw0000gn/T/arduino_build_629528/libraries/Midiboy/MidiboyUSBMIDI.cpp.o
Using previously compiled file: /var/folders/2j/qfqwpm4s51x183j30gf4x0tw0000gn/T/arduino_build_629528/libraries/Midiboy/SH1106.cpp.o
Using previously compiled file: /var/folders/2j/qfqwpm4s51x183j30gf4x0tw0000gn/T/arduino_build_629528/libraries/Midiboy/MidiboyInput.cpp.o
Using previously compiled file: /var/folders/2j/qfqwpm4s51x183j30gf4x0tw0000gn/T/arduino_build_629528/libraries/Midiboy/Midiboy.a
Compiling library "USBMIDI"
Using previously compiled file: /var/folders/2j/qfqwpm4s51x183j30gf4x0tw0000gn/T/arduino_build_629528/libraries/USBMIDI/vusb.S.o
Using previously compiled file: /var/folders/2j/qfqwpm4s51x183j30gf4x0tw0000gn/T/arduino_build_629528/libraries/USBMIDI/vusb.c.o
Using previously compiled file: /var/folders/2j/qfqwpm4s51x183j30gf4x0tw0000gn/T/arduino_build_629528/libraries/USBMIDI/midi_serialization.cpp.o
Using previously compiled file: /var/folders/2j/qfqwpm4s51x183j30gf4x0tw0000gn/T/arduino_build_629528/libraries/USBMIDI/usbmidi_pluggableusb.cpp.o
Using previously compiled file: /var/folders/2j/qfqwpm4s51x183j30gf4x0tw0000gn/T/arduino_build_629528/libraries/USBMIDI/usbmidi_vusb.cpp.o
Using previously compiled file: /var/folders/2j/qfqwpm4s51x183j30gf4x0tw0000gn/T/arduino_build_629528/libraries/USBMIDI/USBMIDI.a
Compiling library "EEPROM"
Compiling library "SPI"
Using previously compiled file: /var/folders/2j/qfqwpm4s51x183j30gf4x0tw0000gn/T/arduino_build_629528/libraries/SPI/SPI.cpp.o
Compiling core...
Using precompiled core: /var/folders/2j/qfqwpm4s51x183j30gf4x0tw0000gn/T/arduino_cache_765248/core/core_Blokas_avr_midiboy_51f02b7210b938436b779d1c032618e1.a
Linking everything together...
/Applications/Arduino.app/Contents/Java/hardware/tools/avr/bin/avr-gcc -w -Os -g -flto -fuse-linker-plugin -Wl,--gc-sections -mmcu=atmega328p -o /var/folders/2j/qfqwpm4s51x183j30gf4x0tw0000gn/T/arduino_build_629528/midimon.ino.elf /var/folders/2j/qfqwpm4s51x183j30gf4x0tw0000gn/T/arduino_build_629528/sketch/midimon_font.c.o /var/folders/2j/qfqwpm4s51x183j30gf4x0tw0000gn/T/arduino_build_629528/sketch/midimon_special_symbols.c.o /var/folders/2j/qfqwpm4s51x183j30gf4x0tw0000gn/T/arduino_build_629528/sketch/midimon.cpp.o /var/folders/2j/qfqwpm4s51x183j30gf4x0tw0000gn/T/arduino_build_629528/sketch/midimon.ino.cpp.o /var/folders/2j/qfqwpm4s51x183j30gf4x0tw0000gn/T/arduino_build_629528/sketch/midimon_event_display_mode.cpp.o /var/folders/2j/qfqwpm4s51x183j30gf4x0tw0000gn/T/arduino_build_629528/sketch/midimon_renderer.cpp.o /var/folders/2j/qfqwpm4s51x183j30gf4x0tw0000gn/T/arduino_build_629528/sketch/midimon_settings.cpp.o /var/folders/2j/qfqwpm4s51x183j30gf4x0tw0000gn/T/arduino_build_629528/sketch/midimon_utils.cpp.o /var/folders/2j/qfqwpm4s51x183j30gf4x0tw0000gn/T/arduino_build_629528/libraries/Midiboy/Midiboy.a /var/folders/2j/qfqwpm4s51x183j30gf4x0tw0000gn/T/arduino_build_629528/libraries/USBMIDI/USBMIDI.a /var/folders/2j/qfqwpm4s51x183j30gf4x0tw0000gn/T/arduino_build_629528/libraries/SPI/SPI.cpp.o /var/folders/2j/qfqwpm4s51x183j30gf4x0tw0000gn/T/arduino_build_629528/../arduino_cache_765248/core/core_Blokas_avr_midiboy_51f02b7210b938436b779d1c032618e1.a -L/var/folders/2j/qfqwpm4s51x183j30gf4x0tw0000gn/T/arduino_build_629528 -lm
/Applications/Arduino.app/Contents/Java/hardware/tools/avr/bin/avr-objcopy -O ihex -j .eeprom --set-section-flags=.eeprom=alloc,load --no-change-warnings --change-section-lma .eeprom=0 /var/folders/2j/qfqwpm4s51x183j30gf4x0tw0000gn/T/arduino_build_629528/midimon.ino.elf /var/folders/2j/qfqwpm4s51x183j30gf4x0tw0000gn/T/arduino_build_629528/midimon.ino.eep
/Applications/Arduino.app/Contents/Java/hardware/tools/avr/bin/avr-objcopy -O ihex -R .eeprom /var/folders/2j/qfqwpm4s51x183j30gf4x0tw0000gn/T/arduino_build_629528/midimon.ino.elf /var/folders/2j/qfqwpm4s51x183j30gf4x0tw0000gn/T/arduino_build_629528/midimon.ino.hex
Using library Midiboy at version 1.0.0 in folder: /Users/tedpedersen/Library/Arduino15/packages/Blokas/hardware/avr/1.0.6/libraries/Midiboy 
Using library USBMIDI at version 1.1.5 in folder: /Users/tedpedersen/Library/Arduino15/packages/Blokas/hardware/avr/1.0.6/libraries/USBMIDI 
Using library EEPROM at version 2.0 in folder: /Applications/Arduino.app/Contents/Java/hardware/arduino/avr/libraries/EEPROM 
Using library SPI at version 1.0 in folder: /Applications/Arduino.app/Contents/Java/hardware/arduino/avr/libraries/SPI 
/Applications/Arduino.app/Contents/Java/hardware/tools/avr/bin/avr-size -A /var/folders/2j/qfqwpm4s51x183j30gf4x0tw0000gn/T/arduino_build_629528/midimon.ino.elf
Sketch uses 13204 bytes (46%) of program storage space. Maximum is 28672 bytes.
Global variables use 683 bytes (33%) of dynamic memory, leaving 1365 bytes for local variables. Maximum is 2048 bytes.
/Applications/Arduino.app/Contents/Java/hardware/tools/avr/bin/avrdude -C/Applications/Arduino.app/Contents/Java/hardware/tools/avr/etc/avrdude.conf -v -patmega328p -cusbasp -PUSB -b115200 -D -Uflash:w:/var/folders/2j/qfqwpm4s51x183j30gf4x0tw0000gn/T/arduino_build_629528/midimon.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 "/Applications/Arduino.app/Contents/Java/hardware/tools/avr/etc/avrdude.conf"
         User configuration file is "/Users/tedpedersen/.avrduderc"
         User configuration file does not exist or is not a regular file, skipping

         Using Port                    : USB
         Using Programmer              : usbasp
         Overriding Baud Rate          : 115200
avrdude: error: could not find USB device with vid=0x16c0 pid=0x5dc vendor='www.fischl.de' product='USBasp'

avrdude done.  Thank you.

the selected serial port 
 does not exist or your board is not connected

This is the actual error - the device is not recognized by your system. We haven’t so far encountered any software reasons on macOS for device not to get recognized, so the most likely cause of the issue is a building mistake somewhere.