Atmel megaAVR, Getting Started

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Board Applications
9-2 megaAVR™ Starter Kit Manual
9.2.1 Misc. Header The last header labeled “Misc.” has connections to processor pins other than the
port pins.
If external operations do not want pull-ups on the port pin, both the switches and the
LEDs can be disconnected from the processor. To isolate the LEDs, remove the jumper
set labeled “Port B”, and to isolate the switches, remove the jumper set labeled “Port D”.
9.3 Using Analog
Functions
The A/D converters use the header labeled “Analog” for the A/D inputs on Port F, which
is input only. A +10V to -10V supply is provided on the connector marked “Op-Amp” next
to the crystal. A lead from this connector can be used for an external amplifier for the
A/D inputs. The layout of the Analog header is shown below.
9.3.1 Analog Port: Marked
on Board
The A/D converters can use either the on-board (Internal) Voltage Reference or an
external Voltage Reference.
9.3.2 Using Internal
Reference To use the internal, on-board Voltage Reference, the pot marked “AREF” is used to set
the voltage level. The voltage level can be measured with a DVM connected to the
BIT 7 OF PORT.
SAME FOR ALL PORTS
EXTRA CONNECTION
FOR V
CC
CUT CORNER
SHOWN ON BOARD
FOR ORIENTATION
BIT 0 OF PORT.
SAME FOR ALL PORTS
EXTRA CONNECTION
FOR GROUND
EXTRA CONNECTION
FOR V
CC
CUT OUT MARKED
ON BOARD
FOR ORIENTATION
EXTRA CONNECTION
FOR GROUND
READ
RD
WRITE
WR
CUT OUT MARKED
ON BOARD
FOR ORIENTATION
ADC0 - ADC7 CONNECTED
TO PORT FPF0 - PF7