INT 15 - TopView - "GETBIT" - DEFINE A 2ND-LEVEL INTERRUPT HANDLER AX = 1013h ES:DI -> FAR service routine Return: BX = bit mask indicating which bit was allocated 0000h if no more bits available SeeAlso: AX=1014h,AX=1015h Note: only a few TopView/DESQview API calls are allowed during a hardware interrupt; if other calls need to be made, the interrupt handler must schedule a 2nd-level interrupt with "SETBIT" (AX=1015h)