4016 DX (250-5001) TEMMDX Faxback Doc. # 1531 Temmdx is an expanded memory manager driver. To use Temmdx: 1. Use the MS-DOS copy command to copy temmdx.sys to your hard disk. 2. Add a device command to your config.sys file: device=\path\temmdx.sys Refer to your MS-DOS documentation if you need more information about the copy command or the device command. Refer to "Using Temmdx" for more information about the Temmdx device command. In order to understand the function of this driver, you need to know the definitions of shadow RAM, expanded memory, and extended memory. SHADOW RAM Your computer is equipped with 1MB (1024KB) of RAM (random access memory) on a 32-bit memory expansion adapter. By adding a second 32-bit memory expansion adapter and filling both adapters with 1MB SIMMs, you can configure your -MORE- system with as much as 16MB of RAM. The first 640KB of RAM in any system is called base RAM. Base RAM is reserved for your operating system and applications. Memory from 640KB to 1024KB (a total of 384KB) is called shadow RAM. Your system BIOS (Basic Input-Output System) uses a portion of shadow RAM. Video adapter BIOS and SCSI BIOS (if applicable to your computer) might also use shadow RAM. The following diagram illustrates base RAM and shadow RAM in a 2MB memory configuration: EXPANDED MEMORY Early microprocessors were not equipped to recognize memory addresses beyond 1MB (1024KB) of memory. When additional memory was required, systems based on such processors relied on expanded memory. Expanded memory was stored on a separate adapter, and it used a different addressing protocol from base and shadow RAM. Expanded memory was accessed in blocks of 16KB. A group of four 16KB blocks is called a page. The blocks in a page are not necessarily adjacent in the available supply of physical expanded memory. The following diagram shows two examples of valid pages. One includes sequential blocks; the other does not. -MORE- EXTENDED MEMORY Current microprocessor technology supports memory beyond 1MB, so expanded memory is no longer required. Instead, current technology uses extended memory, defined as all memory (RAM) beyond the 1MB boundary, to emulate expanded memory. To emulate expanded memory, the processor copies a 64KB page (four 16KB blocks) of extended memory into a 64KB segment of RAM between 640KB and 1024KB. The beginning of the 64KB segment is called the frame address. Since RAM from 640KB to 1024KB is within the 1MB boundary, it is accessible to the processor. The following diagram shows base RAM, shadow RAM, and extended memory: (ext. memory illus.) 1/2 page USING TEMMDX Temmdx.sys uses all extended memory beyond 1MB, plus any shadow RAM not allocated for other purposes, to emulate expanded memory as defined in the LIM (Lotus/Intel/Microsoft) memory specification. -MORE- To use Temmdx: 1. Copy temmdx.sys from the Utilities Diskette to your hard disk. To do this, insert the Utilities Diskette into Drive A and type the following command at the MS-DOS system prompt (A>> or C>>): copy a:temmdx.sys c: Then, press ENTER. 2. Add a device command for Temmdx to your config.sys file. The format for the Temmdx device command is: device = temmdx.sys [/s] [xxxx] [Iy] [Mz] The following table summarizes the Temmdx device command parameters: Switch Function /s Enables the software to access shadow RAM. xxxxx Specifies the amount of expanded memory (in kilobytes) to be emulated. Use a value from 304 to 8192 if you are using /s or 16 to 8192 if you are not using /s. Use a value that is a multiple of 16. The default value is 304KB with /s or 1024KB without /s. -MORE- Iy Identifies the I/O port addresses emulated by temmdx.sys. If one or more hardware boards in your computer access port addresses that conflict with the addresses emulated by temmdx.sys,use the following chart to select addresses that can be emulated without conflict. The default y value is 5. y Value Port Addresses Used (Hex) 0 208 4208 8208 C208 1 218 4218 8218 C218 5 258 4258 8258 C258 6 268 4268 8268 C268 10 2A8 42A8 82A8 C2A8 11 2B8 42B8 82B8 C2B8 14 2E8 42E8 82E8 C2E8 Mz Specifies the base frame address for temmdx.sys to use for LIM page mapping. The default z value is 3. z Value Frame Address (Hex) 0 C400-D400 1 C800-D800 2 CC00-DC00 -MORE- 3 D000-E000 4 D400-E400 5 D800-E800 6 DC00-EC00 7 E000-F000 NOTES: * Do not use temmdx.sys with software that uses the advanced features of the 80386 processor. * If you want to use expanded memory with other device drivers, the temmdx.sys device com- mand must be the first device command in your config.sys file. See your operating system documentation for more information. * Do not use a frame address that overlaps addresses used by the hardware. RUNNING UTILITIES FROM MS-DOS Use the MS-DOS copy command to copy utilities from the Utilities Diskette to your hard disk or to an MS-DOS diskette. For example, to copy the Setup -MORE- utility to hard disk Drive C, type: copy a:setupdx.com c: and press ENTER. To run utilities from the MS-DOS diskette, insert the MS-DOS diskette into a diskette drive. Then, at the MS-DOS operating system prompt (such as A>>), type the program name that corresponds to the desired utility. To run utilities from a hard disk, type the appropriate program name at the hard disk prompt (such as C>>). It is not necessary to enter the file extension, such as .com, to run a utility. The following utilities can be copied from the Utilities Diskette and run from the MS-DOS prompt: Utility Program Name Setup setupdx.com Keyboard password kp.exe CPU speed* speed16.com Video mode control* vga.exe * Advanced utilities The Utilities Diskette also includes temmdx.sys, an extended memory manager. Refer to "Temmdx" for more information about using the driver. To copy temmdx.sys and all the utilities in the preceding table to your hard disk, type: copy a:*.* c: and press ENTER.