INT F1 - Common ISDN API(Application Program[ming] Interface) The defined set of calls which a program may make to interact with or request services of the operating system or environment under which it is running. Because the inputs and outputs of the calls are well-defined, a program using the API can continue using the identical calls even if the internal organization of the program providing the API changes. (CAPI) v1.1 - "API-REGISTER" - INITIALIZE CAPI AH = 01h ES:BX -> buffer for CAPI's use (refer to note below) CX = minimum number of pending messages DX = maximum simultaneous Level 3 connections SI = maximum concurrent received B3 data blocks DI = maximum B3 data block size Return: AX = CAPI-assigned application ID 0000h on error BX = error number 1001h registration error Range: INT 00 to INT FF, selectable by program parameter Notes: the caller is required to provide at least 512 bytes of stack space the CAPI interrupt handler begins with a header which is nearly identical to the IBMInternational Busiuness MachinesInternational Busiuness Machines) A hardware, software and other service technology company founded in 1911. Interrupt Sharing Protocol header (see #02568 at INT 2D"AMISAlternate Multiplex Interrupt Specification"), except that the short jump instruction to a hardware reset handler at offset 09h is replaced by the signature bytes "IA" the maximum length of a message is fixed at 180 bytes; the standard document suggests using CX=10, DI=1, SI=7, and DI=130 for applications which use only a single connection and standard protocols the total size of the application-provided buffer must be at least 180*CX + DX*SI*DI bytes SeeAlso: AH=02h,INT F1/AL=01h Index: installation check;Common ISDN API(Application Program[ming] Interface) The defined set of calls which a program may make to interact with or request services of the operating system or environment under which it is running. Because the inputs and outputs of the calls are well-defined, a program using the API can continue using the identical calls even if the internal organization of the program providing the API changes.