INT 2F U - DR DOS 6+, Novell DOS 7+ - EMM386.EXE - VIDEO MEMORY SPACE CONTROL AX = 12FFh BX = 0006h DX = 0000h CX = function 0000h get status of video memory space (MEMMAX /V) 0001h map memory into video memory space (MEMMAX +V) 0002h unmap memory from video memory space (MEMMAX -V) Return: CF clear if successful AX = 0000h (successful) BX = segment of reserved video RAM(Random Access Memory) See also DRAM, SRAM. CX = segment of used video RAM(Random Access Memory) See also DRAM, SRAM. DX = segment of first upper MCBsee Memory Control Block Notes: this functionality is provided by EMM386, and partially supported by HIDOS.SYS BL specifies which program handles the call, BH is the function number BUG: 4DOS 5.51(a) often hangs the system (reported to be reproducable), if MEMMAX +V is issued from the 4DOS prompt. To avoid this, one should temporary load COMMAND.COM followed by MEMMAX +v , starting the application, MEMMAX -v and EXIT. 4DOS 5.5c does not show this phenomena on the same systems where 5.51a hangs. SeeAlso: AX=D201h/BX=4849h (Table 04105) Values for DR DOS memory space control error code: 00h successful 80h video memory already unmapped 81h video memory already mapped 82h no video memory reserved (/VIDEO not specified) 83h video memory in use (graphics mode or non-standard text mode) 84h mapped video memory contains allocated arena(s) 85h hardware error 86h driver requires protected mode but is permanently in real mode ("EMM386 OFF")