Microcontroller Configuration - QRP Labs QLG2 Manual

3.11 Microcontroller configuration

The 2 x 5 pads near the microcontroller chip, configure the operation of the microcontroller.
These jumpers are "read" by the microcontroller at power-up in order to determine the
configuration. Thereafter, they are ignored; therefore if a jumper plug is removed (for
example) after power-up, nothing will happen until the next time the power is removed and
applied again to the board.
By default, none of these pads have any connection (no tinned copper traces on the
underside of the board). The nomenclature PA4, PA0 etc is a reference to the port pins of
the microcontroller. PA7, PA6 and PA5 are currently unused.
The operation of these configuration jumpers is:
PA4: Bootloader
JUMPER: Causes the microcontroller to enter the bootloader (see section below)
OPEN: Causes the microcontroller to run the normal USB to Serial converters
PA0: Baud rate
JUMPER: Baud rate is set to 38,400 (suitable for QCX CAT)
OPEN: Baud rate is set to 9,600 (suitable for default GNSS module communication)
Example configuration for CAT control of a QCX-series CW transceiver:
QLG2 manual for firmware 1.00a
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