INT 20 P - Microsoft Windows - BlockDev / IOS - 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. = 0010h
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 01278)
Values for BlockDev/IOS (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 0010h) service number:
 0000h	get version
 0001h	register device
 0002h	find INT 13 drive
 0003h	get device list
 0004h	send command
 0005h	command complete
 0006h	synchronous command
 0007h	"IOS_Register"
 0008h	"IOS_Requestor_Service"
 0009h	"IOS_Exclusive_Access"
 000Ah	"IOS_Send_Next_Command"
 000Bh	"IOS_Set_Async_Time_Out"
 000Ch	"IOS_Signal_Semaphore_No_Switch"
 000Dh	"IOSIdleStatus"
 000Eh	"IOSMapIORSToI24"
 000Fh	"IOSMapIORSToI21"
 0010h	"PrintLog"
SeeAlso: #01277,#01279