Leonardo hangs on upload with RX on

[rpreliasco]

Hello,

I have a Leonardo which will not accept new sketches. There is a sketch loaded that executes when reset is pressed, but when I try to upload a new sketch, the RX lights up continuously and that's it. I get no error messages from the IDE output. Pressing reset will turn off the light but the same thing happens when uploading is attempted.

I know the cable and com port is good because I have another Leonardo that will upload with the same connection. There is nothing attached to pins 0 or 1.

It was working OK until the current sketch was uploaded.

[rpreliasco]

Update: I tried uploading "blink" with the cloud-based IDE and got the following messages:

Upload started

Programming with: Serial

Restarting in bootloader mode

Flashing with command:C:/Users/dpreliasco/.arduino-create/arduino/avrdude/6.3.0-arduino17/bin/avrdude.exe -CC:/Users/dpreliasco/.arduino-create/arduino/avrdude/6.3.0-arduino17/etc/avrdude.conf -v -patmega32u4 -cavr109 -PCOM9 -b57600 -D -Uflash:w:C:/Users/DPRELI~1/AppData/Local/Temp/arduino-create-agent005069387/Blink.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 "C:/Users/dpreliasco/.arduino-create/arduino/avrdude/6.3.0-arduino17/etc/avrdude.conf"

Using Port : COM9

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: .avrdude: butterfly_recv(): programmer is not responding

avrdude: butterfly_recv(): programmer is not responding

[rpreliasco]

Update update: I finally was able to unbrick it after many tries at pressing the reset button just before uploading. I guess getting the timing right is a matter of luck.