Which pins are not used?

Posts: 9
Joined: Fri Jun 24, 2011 9:24 pm

Which pins are not used?

Post by sean »


The silkscreen on the board says "PINS IN USE" beneath pins 13, 12, 11, and 10, and there is a box around 9 that seems to include that pin.

Looking in the schematic, however, it seems that 9 is not used, and 7 is used. (10-13 appear to be used and correctly marked on the PCB.)

Which pins should be considered in use and off-limits to development?

Posts: 7
Joined: Tue Nov 08, 2011 12:41 am

Re: Which pins are not used?

Post by dan77062 »

I have the same question-- Cannot find a list of which pins are available for development.
It seems clear that A0 - A7 are OK.
If it follows the UNO format, then pins 0 and 1 are for serial tx/rx, then 2 - 8 are OK for general IO, with 3,5,6 OK for PWM.
Looks like pins 9 - 13 are not available, is that correct?
Thanks for the help.

9 is connected to the Max chip interrput but it really isn't used in the software, so 9 is fair game.
Arduino 7 is in use as a reset line for the Max chip.

So the free pins on the Host Board are Arduino pins 0-6, 8,9, 14-21 (AKA A0 through A7)
Please note that pins 20, 21 (A6, A7) can not be used as GPIO but work fine as analog inputs. They also don't have pullup resistors available.


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