Firmware reloading newb question Creality Ender 3 Pro

What is the problem?

When updating firmware using the Octoprint "firmware updater" plugin, did you use a burner hardware kit such as the ISP USB and pin adapter provided with Creality's BLTouch upgrade kit, or just the normal Octoprint USB connection? The latter appears not to work.

What did you already try to solve it?

Tried connecting via normal Octoprint USB connection, but AvrDude fails to sync.

Logs

When I choose the file provided as an update from Creality, Ender-3 Pro1.1.6BLTouchV3PowerLossContinueEnglish.hex, and select Flash from File, I get a batch of these errors after a few seconds:

Avrdude says: 'not in sync: resp=0x65
avrdude: stk500_getsync() attempt 2 of 10: not in sync: resp=0x63
avrdude: stk500_getsync() attempt 3 of 10: not in sync: resp=0x68
...

Here is the Terminal output from this time:

Recv: T:18.20 /0.00 B:18.12 /0.00 @:0 B@:0
Recv: T:18.40 /0.00 B:18.12 /0.00 @:0 B@:0
Recv: T:18.24 /0.00 B:18.12 /0.00 @:0 B@:0
Connection closed, closing down monitor
Changing monitoring state from "Operational" to "Offline"
Connecting to: /dev/ttyUSB0
Changing monitoring state from "Offline" to "Opening serial port"
Connected to: Serial<id=0x6b026590, open=True>(port='/dev/ttyUSB0', baudrate=115200, bytesize=8, parity='N', stopbits=1, timeout=10.0, xonxoff=False, rtscts=False, dsrdtr=False), starting monitor
Changing monitoring state from "Opening serial port" to "Connecting"
Send: N0 M110 N0125
Send: N0 M110 N0
125
Recv: Error:No Line Number with checksum, Last Line: 0
Recv: ok
Changing monitoring state from "Connecting" to "Operational"
Send: N0 M110 N0125
Recv: ok
Send: N1 M115
39
Recv: FIRMWARE_NAME:Marlin Creality 3D SOURCE_CODE_URL:https://github.com/MarlinFirmware/Marlin PROTOCOL_VERSION:1.0 MACHINE_TYPE:Ender-3 Pro EXTRUDER_COUNT:1 UUID:cede2a2f-41a2-4748-9b12-c55c62f367ff
Recv: Cap:EEPROM:1
Recv: Cap:AUTOREPORT_TEMP:1
Recv: Cap:PROGRESS:0
Recv: Cap:PRINT_JOB:1
Recv: Cap:AUTOLEVEL:0
Recv: Cap:Z_PROBE:0
Recv: Cap:LEVELING_DATA:0
Recv: Cap:SOFTWARE_POWER:0
Recv: Cap:TOGGLE_LIGHTS:0
Recv: Cap:CASE_LIGHT_BRIGHTNESS:0
Recv: Cap:EMERGENCY_PARSER:0
Recv: ok
Send: M21
Recv: echo:TF card ok
Recv: Init power off infomation.
Recv: size:
Recv: 585
Recv: init valid:
Recv: 0
Recv: 0
Recv: ok
Send: M876 P1
Recv: ok
Send: M155 S2
Recv: ok
Recv: T:18.40 /0.00 B:18.12 /0.00 @:0 B@:0
Recv: T:18.32 /0.00 B:18.12 /0.00 @:0 B@:0
Recv: T:18.36 /0.00 B:18.12 /0.00 @:0 B@:0

TIA if anyone can help.

Additional information about your setup

OctoPrint 1.4.0 (updated from 1.3) and "Firmware updater" (installed this week from Octoprint plugin manager). OctoPI with a Pi 3 talking WiFi from my browser to the Pi and USB cable from Pi to the Creality Ender 3 Pro. Printer's "About" advises firmware 1.1.6.2.

Firmware Updater plugin. Settings:
Flash Method: avrdude
AVR MCU ATmega1284p
Path to avrdude: /usr/bin/avrdude (Test says path is valid)
AVR Type arduino

Hey

Ender 3 doesn't have a bootloader, so connecting directly to computer for update will not work. You'll need a harware flasher first, with witch you'll be able to write a new firmware WITH bootloader. From then one standard usb connection will do.

See https://www.youtube.com/watch?v=Hi7uPYJ_q-U