EMM386 command
Updated: 11/12/2023 by Computer Hope
Also know as EMM386.EXE, EMM386 is an Extended Memory Manager used with Intel 80386 and above processors. This program allows MS-DOS computers to have more than 640 KB of memory.
Availability
The EMM386 file is an external command in MS-DOS and is available for the following versions of Windows and MS-DOS as emm386.exe.
EMM386 syntax
Turns on or off EMM386 expanded memory support.
EMM386 [ON | OFF | AUTO] [W=ON | W=OFF]
| ON | OFF | AUTO | Activates or suspends EMM386.EXE device driver, or places it in auto mode. |
| W=ON | OFF | Turns on or off Weitek coprocessor support. |
EMM386 examples
EMM386
Typed alone would load the extended memory manager, usually by default this would be loaded in the autoexec.bat.
EMM386 error messages
| EMM386 error number | Description |
|---|---|
| 0 | Divide Error |
| 1 | Debugger interrupt |
| 2 | Non-maskable interrupt |
| 3 | Breakpoint |
| 4 | Overflow interrupt |
| 5 | Array boundary violation. |
| 6 | Invalid Opcode |
| 7 | Coprocessor not available. |
| 8 | Double fault |
| 9 | Coprocessor segment overran. |
| 10 | Invalid task statement. |
| 11 | Segment not present. |
| 12 | Stack exception. To resolve error 12 from C:\> type edit config.sys and add "STACKS=16,256" to the file. If you already have a stacks line in the config.sys, ensure it equals 16,256. |
| 13 | General violation. Error 13 is an indication that program or driver is using protected mode without cooperating with EMM386. You may need to obtain VCPI-compliant version of the program or driver from your vendor to correct this error message. |
| 14 | Page fault. |
| 16 | Coprocessor error. |