FDXMS Ü ßßßßßß Manages the use of extended memory. FDXMS.SYS manages programs' use of extended memory and of the high memory area (HMA). This prevents programs from simultaneously using the same area of memory. You install the FDXMS.SYS device driver by adding a device command for FDXMS.SYS must precede any device command for programs or device drivers that use extended memory. Syntax: DEVICE=[drive:][path]fdxms.sys [/hmamin=m] [/numhandles=n] [/int15=xxx] [/a20control:on|off] [/shadowram:on|off] [/cpulock:on|off] [drive:][path] Specifies the location of the FDXMS.SYS file. /hmamin=m Specifies the amount of memory (in kilobytes) a program must use before FDXMS.SYS permits the program to use the high memory area. Valid values for m are 0-63. The default value is 0. /numhandles=n Specifies the maximum number of extended-memory-block (EMB) handles that can be used simultaneously. Valid values for n are 1-128. The default value is 32. Each additional handle requires an additional 6 bytes of resident memory. /int15=xxx Allocates the specified amount of extended memory (in kilobytes) for the Interrupt 15h interface. Some older programs use a conflicting extended-memory scheme. To ensure enough memory is available, add 64 to the value you want to specify for xxx. Valid values for xxx are 64-65535. If you specify a value that is less than 64, the value becomes 0. The default value is 0. /a20control:on|off Specifies whether FDXMS.SYS is to take control of the A20 line even if A20 was on when FDXMS.SYS was loaded. If you specify /a20control:off, FDXMS.SYS takes control of the A20 line only if A20 was off when FDXMS.SYS was loaded. The default setting is /a20control:on. /shadowram:on|off Specifies whether FDXMS.SYS is to switch off shadow RAM - Random Access Memory (RAM) used for read-only memory (ROM) - and add that RAM to its memory pool. If your computer has less than 2 megabytes of RAM, the default setting is /shadowram:off. This parameter is supported only on some computers. /cpulock:on|off Specifies whether FDXMS.SYS is to affect the clock speed of your computer. If your computer's speed changes when you install FDXMS.SYS, specifying the /cpulock:on might correct the problem. Enabling this switch slows down FDXMS.SYS. Example: To install FDXMS.SYS, using the default values, add the following line to your CONFIG.SYS file: device=fdxms.sys Since no location is specified, FreeDOS searches for FDXMS.SYS in the root directory of your startup drive.