The HP palmtop has one PCMCIA Type II Version 2 slot.
Electrically the card slot conforms to the PCMCIA 2.x standard. In particular, the hardware supports both memory and IO cards.
The PCMCIA controller in the HP Palmtop is proprietary and unique to the HP Palmtop. Documentation for the controller is contained in the Cougar System Controller chapter of this guide.
In reading the documentation, see a table near the front of the chapter for the GPIO lines that go to the card slot.