Atmel STK200, Manual

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In-System Programming
10-2 STK200 Starter Kit
10.2 ISP Header
Layout
Note: This is a view of the header needed on user circuit, not a face view of ISP lead.
10.3 Interface Using
Resistors
Typical resistor values would be 1K. This circuit is fine if ports PB7, PB6 and PB5 are
used as inputs in your circuit. If outputs are needed, especially higher than a few milli-
amps, then the multiplexed circuit is preferable.
10.4 Using an Analog
Multiplexer IC
The multiplexer select can be driven from the LED connection on the programming lead
as can a low-power LED with its cathode connected to the LED connection via a suitable
resistor—1K
Ω
is fine. If you use this connection, then the output will be low 0 during pro-
gramming and a 1 at all other times. Note that it will float if the programmer is not active,
i.e., the software is not running so you may need to use a pull-up resistor.
All the pins, except ground, will float if the programmer is not active. The device may
then be programmed in the normal way.
OPTIONAL PROGRAM
INDICATOR CIRCUIT