Firmware version 1.0

This firmware reads analog values only on ADC0 and the configuration menu looks as shown below. The buttons to access the menu are

PB0 = connect to gnd at boot time to enter the configuration menu
PD7 = next
PD6 = increase value
PD5 = decrease value

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           V
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setup pin -> GND at power on
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   module enters setup mode
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    next pin -> GND
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module shows raw  analog digital converter
readings.
ADC0 with 12bit accuracy. The display shows
"a0:" followed by numbers between 0 and 4092.
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    next pin -> GND
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Module shows "D:" and you can use the
pins "+" and "-" to change the value for
the divider. Touch "+" or "-" with a GND
connected wire to step the value up or down
and connect the wire for a longer time to
fast scroll up or down.
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    next pin -> GND
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Module shows "M:" and you can use the
pins "+" and "-" to change the value for
the multiplier. The handling is the same
as described above for "D:".
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    next pin -> GND
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Module shows "A:" and you can use the
pins "+" and "-" to change the value for
the add or subtract constant.
The handling is the same as described above
for "D:".
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    next pin -> GND
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Module shows "P:" and you can use the
pins "+" and "-" to change the value for
the amount of digits behind decimal point.
The handling is the same as described above
for "D:".
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    next pin -> GND
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Module shows "c0:none" and you can use the
pins "+" and "-" to change the "none" into
a letter (can be used to display the
measurement unit).
Possible letters are one of the following:
ABCDEFGHIJKLMNOPQRSTUVWXYZ '%$
abcdefghijklmnopqrstuvwxyz
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    next pin -> GND
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Module shows "c1:none" and you can use the
pins "+" and "-" to change the "none" into
a second letter (can be used to display the
measurement unit).
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    next pin -> GND
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The values are stored permanently in
EEPROM and the module shows "done" in
the display. Power-cycle the module.