Most embedded System-on-chips come with an UART or TTL integrated into the System-on-chip to allow debugging, firmware replacement or serial connection.
The GnuBee Personal Cloud routes the UART connection to a 3.5mm (1/8") Audio Jack for convenient use.
V1.0 uses a Winchiphead CH340G USB to serial chip from Nanjing QinHeng Electronics Co.,Ltd. to convert the UART signal to USB.
The Linux kernel identifies this chipset as the "QinHeng Electronics HL-340 USB-Serial adapter"
The GnuBee USB to UART V1.0 can be identified by the metal 3.5mm (1/8") Plug.
V1.1 uses a Prolific PL2303HXD USB to serial chip to convert the UART signal to USB.
The Linux kernel identifies this chipset as the "Prolific Technology, Inc. PL2303 Serial Port"
The GnuBee USB to UART V1.1 can be identified by the molded plastic 3.5mm (1/8") Plug.
Users of other Operating Systems can find drivers in the drivers directory.
Common methods to change firmware in case of any problems.
I use [GNU Screen]https://www.gnu.org/software/screen/ AND [tftpd-hpa]https://packages.debian.org/buster/tftpd-hpa
screen /dev/ttyUSB0 57600
Fedora users may need to use sudo in front of screen, if you get a [screen is terminating] message.
Windows users can download an install PuTTY AND TFTP32)
Baud Rate: 57600 / Data Bits: 8 / Parity Control: NO / Stop Bits: 1 / Handshake: NO
It is possible to replace the CH340G with a PL2303 USB to UART. Remove the cable from the USB connector, strip back the wires and attach colours GND=Black, TX=green, RX=white. If you prefer an image..
