Sixty Four Pixels Arpie, User Manual

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There are several other connectors and indicators on the lower board which are
used less often, and sometimes only for diagnostic purposes. These are as shown
below
•
The Power LED should be on the whole time Arpie is being powered
•
The hack header breaks out 5V power and four spare I/O lines from Arpie ’s
microcontroller. It allows DIY add- ons or connection of “tab” expansion
boards, as described later.
•
The programming header is used to load new firmware on to the Arpie
processor using a suitable USB programmer.
•
Diagnostic LED 1 is connected to the main ATMega328P microcontroller -
Arpie's "brain". When the brain is alive, this LED should blink about once per
second.
•
Diagnostic LED 2 is connected to the PIC12F1822 microcontroller that
manages the aux midi port. This LED should blink every two seconds.
•
PIC Programming Header can be used to update firmware on the PIC chip,
using a PICKit2 type programmer. Usually it would be rare to need to do this,
and typically there is no need to solder a header here.