Hi Dario,
I went and bought a micro HDMI cable. I am pretty sure my bootloader is fine as I see the logo. Also when I tried it today it no longer hangs at 37% but uploads 100% but still fails with a Sam BA operation failed
checksumBuffer(start_addr=0x98000, size=0x1000) = e03e
checksumBuffer(start_addr=0x99000, size=0x1000) = e03e
checksumBuffer(start_addr=0x9a000, size=0x1000) = e03e
checksumBuffer(start_addr=0x9b000, size=0x1000) = e03e
checksumBuffer(start_addr=0x9c000, size=0x1000) = e03e
checksumBuffer(start_addr=0x9d000, size=0x1000) = e03e
SAM-BA operation failed
checksumBuffer(start_addr=0x9e000, size=0x1000) = e03e
checksumBuffer(start_addr=0x9f000, size=0x1000) = e03e
checksumBuffer(start_addr=0xa0000, size=0x1000) = e03e
checksumBuffer(start_addr=0xa1000, size=0x1000) = a701
checksumBuffer(start_addr=0xa2000, size=0x1000) = 314b
checksumBuffer(start_addr=0xa3000, size=0x1000) = 9055
checksumBuffer(start_addr=0xa4000, size=0x1000) = 94e5
checksumBuffer(start_addr=0xa5000, size=0x844) = 704e
Verify successful
done in 32.933 seconds
CPU reset.
readWord(addr=0)=0x20007ffc
readWord(addr=0xe000ed00)=0x410cc601
readWord(addr=0x41002018)=0x10010305
writeWord(addr=0xe000ed0c,value=0x5fa0004)
An error occurred while uploading the sketch