A little about the Prop-2

[JonnyMac]

Processor	Parallax BASIC Stamp 2
Speed (instructions per second)	~4000
I/O Connections	16 + Serial
RAM (variables)	26 + 6
Program Memory (bytes)	2048
Program Length (instructions)	~500
PBASIC Commands	42
Programming Connection	Serial, 9600 baud
Windows IDE?	Yes; Parallax
Mac IDE?	Yes; 3rd party

[DougLowe]

The Prop-2 looks great so far Jon!

Can you shed some light on the setup DIPs?

[JonnyMac]

Sure.  The SETUP jumpers on P12..P15 allow the user to selectively set either of these input pins to a known state.  In the DN position, the associated I/O pin is pulled to ground through a 4.7K resistor; this would be the setting for an active-high input.  In the UP position, the I/O pin is pulled to Vdd (+5v); this is good for active-low inputs.  The key here is that inputs should not be left to "float" in an unknown state, they should be pulled to the idle state appropriate for the connected input.

The schematic below shows the configuration of the P12 I/O pin.  P13..P15 are identical.