Globalscale Motherboards

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Marvell ESPRESSObin SBC, on a Globalscale Motherboard.

Notable features:

High bandwidth/throughput and a healthy selection of transport options, ~$70US.  Low levels of support, but Armbian and OpenWRT at least used to offer images.

Identification:

v7 has v7 printed on the board on the bottom(the side opposite from where Ethernet Cables plug in) just right of the double Ethernet Jacks.  Memory size was located on a sticker over one of the Ethernet Jacks, for me.  Ram chips are just in from the micro USB port on both sides of the board, if only one is populated then you've one RAM chip otherwise there are two.

A 12v PSU is required using a standard power jack:

5.5×2.1mm

standard configuration: Core = + , Outside = GND/-

12V @2A

Serial Console is a USB UART accessible via a Female Micro-USB B, not powered via USB.  Every-time you remove the 12V power the USB slave/client device disconnects, leaving whatever software that was using it in an unknown state.  Over this UART the POST prints stuff, so it's not suitable for driving a Modem, for example.

When recovering the board using Bootloader recovery via UART you've two seconds to interrupt the boot, after the upload completes...  Where this upload can take a few minuets and you've to be attentive the entire time as once the upload completes you've little time to start your terminal/connect/and press the proverbial any key.  Also don't forget `stty -F /dev/ttyUSB${1:0} clocal`.

I use `cu --line /dev/ttyUSB${1:-0} --speed 115200 --nostop --nortscts` in a script on a Raspberry Pi Zero W(using a Micro USB to Micro USB OTG Cable), making the TTY wireless.  `cu` needs to be installed, but it's old and sturdy.

# Note: the special sequence `${1:0}` means the same as `<Port #>`, but is specially understood by BASH to mean `First cmdline parameter OR "0"`.  This gives 0 as a reasonable default Port #, but allows another port to be used.  Actually I'm not sure where `<Port #>` comes from, it's a throwback to when communication ports(COM/ports) had numbers.  They don't anymore so it's basically a guessing game if your system has more than one.