IO source/sink specs

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>Im new to the Armmite Pro and this forum, and I did do a quick search before
posting, but does anyone know if the Armmite Pro can Source or Sink on Output?
I'd like to "drive" a PNP transistor using HWPWM.

The answer is really the same for any 3V or 5V TTL device. These outputs both
sync and source current (4 mA in the LPC2103 case).

BUT !!

What you really want to know is can the output pulldown on the base of a PNP
device, and the answer here may be no. As the typical application will have the
PNP transistor tied to a high voltage supply (most likely much more that 5V,
probably 12V). In this case the parasitic diode of the output will always be
there and turn on the PNP transistor.

So to drive a PNP transistor you need a true open collector / open drain device
without the parasitic diode. So something like an open collector buffer like a
7406 or just some NPN transistor like a 2N3904 with a series resistor to the
base.

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probably more information than you need to know

http://focus.ti.com/lit/an/sdya009c/sdya009c.pdf

section 2.1 covers CMOS devices which the LPC2103 is, and they have diodes from
the outputs and inputs to the supply rail.

While the LPC2103 has inputs specifically designed to tolerate 5 V signals,
remember that's SIGNALs, not power supplies, so you can't tie them to low
impedance sources greater than 3.3V.

In this case a PNP transistor looks like a pretty low impedance source,
basically it looks like a diode from emitter (supply) to the base.