The BASIC Stamp 2px

http://www.parallax.com/detail.asp?product_id=BS2PX-IC

The BASIC Stamp 2px module (BS2PX24) is the highest performing of all the BASIC Stamp microcontrollers, running nearly 1.6 times faster than the BASIC Stamp 2p. The BS2px includes a built-in voltage comparator, as well as user-configurable Pull-up Resistor, Schmitt Trigger, and Logic Threshold circuitry on every I/O pin. In order to use the BASIC Stamp 2px.