The API for both the HP 95LX and other HP palmtops are supported simultaneously by the HP palmtop System Manager. Where necessary to distinguish between the two versions of API, "API1" and "API2" will be used, otherwise "API" refers to API2. To compile API2 applications, the C compile time switch /DAPI2 needs to be added to the compiler options. Note that API2 uses Int 7Eh as the interrupt of communication between the applications and the System Manager, while the API1 in the HP 95LX uses Int 60h.