INT 20 P - Microsoft Windows - V86MMGR - VxDA virtual device driver for Windows 3.x or 95. So called because nearly all of the Windows 3.0 drivers had names of the form "VdeviceD". See also device driver. SERVICES VxDA virtual device driver for Windows 3.x or 95. So called because nearly all of the Windows 3.0 drivers had names of the form "VdeviceD". See also device driver. = 0006h Note: the desired VxDA virtual device driver for Windows 3.x or 95. So called because nearly all of the Windows 3.0 drivers had names of the form "VdeviceD". See also device driver. and service number are identified by the data immediately following the INT 20 instruction, as in: INT 20h DW service number DW VxDA virtual device driver for Windows 3.x or 95. So called because nearly all of the Windows 3.0 drivers had names of the form "VdeviceD". See also device driver. identifier SeeAlso: INT 2F/AX=1684h"DEVICE 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.",INT 30"Windows",#01265,#01340 (Table 01270) Values for V86MMGR (VxDA virtual device driver for Windows 3.x or 95. So called because nearly all of the Windows 3.0 drivers had names of the form "VdeviceD". See also device driver. ID 0006h) service number: 00h get version 01h allocate V86see Virtual-86 Mode pages 02h set EMSsee Expanded Memory Specification and XMSsee Extended Memory Specification limits 03h get EMSsee Expanded Memory Specification and XMSsee Extended Memory Specification limits 04h set mapping information 05h get mapping information 06h Xlat 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. 07h load client pointer 08h allocate buffer 09h free buffer 0Ah get Xlat buffer state 0Bh set Xlat buffer state 0Ch get VMsee Virtual Machine flat selector 0Dh map pages 0Eh free page map region 0Fh _LocalGlobalReg 10h get page status 11h set local A20(Address line 20) The 80286 and higher CPUs allow addresses in real mode to extend slightly beyond the one megabyte mark, which causes an incompatibility with some older programs which expect such addresses to wrap back to the beginning of the address space. For complete compatibility with the 8088, newer machines thus contain circuitry which permits the twenty-first address line (A20) to be disabled. The CPU then effectively has only twenty address lines in real mode, just as the 8088 does, and addresses which would extend beyond the one megabyte mark wrap to the beginning of the address space. See also High Memory Area, Real Mode. 12h reset base pages 13h set available mapped pages 14h "V86MMGR_NoUMBInitCalls" 15h "V86MMGR_Get_EMS_XMS_Avail" 16h "V86MMGR_Toggle_HMA" EAX = ??? 17h "V86MMGR_Dev_Init" 18h "V86MMGR_Alloc_UM_Page" SeeAlso: #02646,#01271,INT 2F/AX=1684h"DEVICE 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."