EMS DRIVER

1991 · driver · utility

PART 1: INTRODUCTION There are 4 files on the diskette. 1. SATSW.EXE A utility program to select the operating parameters of the system board. 2. SHADOW.EXE A utility program for using shadow RAM on the system board. 3. EMMSAT.SYS A device driver for using EMS. 4. READ.ME The file that you are reading. PART 2: Using the SATSW Utility Program The core of the system board is a chip called 'SAT'. There- fore this utility is called SATSW. This program let you change the operating parameters of the system board. There are altogether 4 options. You may choose these options by typing SATSW and use the built-in menu. Alterna- tively, you may select the options by supplying parameters on the command line. The 4 options are as follow: 1. Set CPU Clock rate The CPU clock can be switched between 6 Mhz, 8 Mhz, 12 Mhz and 16 Mhz. You should only select 16 Mhz when your motherboard supports it. Otherwise the system may clash. 2. Set I/O bus parameters For the original AT design, the I/O bus are running at 8 Mhz. For 16 bit access, 1 wait state is inserted. For 8 bit access, 4 wait states are inserted. Moreover, for 8 bit memory and all I/O accesses, the command signals are delayed by 1 processor clock. To maintain maximum compatibility with add-on cards, the CPU will be slowed down to 8 Mhz when accessing devices on the I/O bus. This feature is call dynamic clock switching (DCS). If you have enabled DCS, the recommended values for the parameters are as follows : 16 BIT WAIT STATE : 1 8 BIT WAIT STATE : 4 16 BIT COMMAND DELAY : 0 8 BIT COMMAND DELAY : 1 For fast expansion cards, DCS may be disabled for better performance. This time the recommended values are as follows : 16 BIT WAIT STATE : 3 8 BIT WAIT STATE : 7 16 BIT COMMAND DELAY : 0 8 BIT COMMAND DELAY : 1 You may change the values if you are sure that the cards will work. 3. Set RAM wait state System is fastest when running at 0 wait state. Normal AT runs at 1 wait state. 4. Set ROM wait state For safety the ROM is set to run at 4 wait states at turbo mode. With 250 ns ROM, you can set it to run at 2 wait states at 12 Mhz CPU clock and 3 wait states at 16 Mhz. To select options on the command line, type the following : SATSW C6 : Set CPU clock to 6 Mhz SATSW C8 : Set CPU clock to 8 Mhz SATSW C12 : Set CPU clock to 12 Mhz SATSW C16 : Set CPU clock to 16 Mhz SATSW W16x : Set I/O BUS 16 bit wait state to x (1-7) SATSW W8x : Set I/O BUS 8 bit wait state to x (2-7) SATSW D16x : Set I/O BUS 16 bit command delay to x (0-3) SATSW D8x : Set I/O BUS 8 bit command delay to x (0-3) SATSW BDON : enable I/O BUS dynamic clock switching SATSW BDOFF : disable I/O BUS dynamic clock switching SATSW R0 : Set RAM to 0 wait state SATSW R1 : Set RAM to 1 wait state SATSW Mx : Set ROM wait state to x (2-7) PART 3: Using SHADOW utility program Program will run faster in RAM than in ROM. For EGA and VGA display cards, the video BIOS is placed in ROM. To improve performance, the system board allows you to copy the contents of ROM into RAM and execute the code out of RAM. The same applies to the system BIOS. The SHADOW utility allows you to shadow the video or system BIOS. You may make these selection by typing SHADOW and use the built-in menu. Alternatively, you may select the options by supplying parameters on the command line as follows : SHADOW V : Shadow video BIOS (C0000H-C7FFFH) SHADOW S : Shadow system BIOS (F0000H-FFFFFH) SHADOW NV : Not shadow video BIOS (C0000H-C7FFFH) SHADOW NS : Not shadow system BIOS (F0000H-FFFFFH) When you enable shadow RAM, 384 K or extended RAM will be taken away. Before enable shadow RAM ,You should not load any program which use extended memory. With shadow RAM enabled, sometimes the BIOS will report 'memory size mismatch' error on warm start. You should ignore this message and should not perform any set up. Also, if you have installed RAM card which support extended memory, you should not use this utility. (EMS RAM card is OK). Please read PART 4 if you want to use EMS together with shadow RAM. If 4464 is used to implement 640 K configuration, the shadow RAM feature is NOT available. PART 4 : SAT EMS 4.0 DOCUMENTATION The SAT EMS 4.0 device driver is a standard MSDOS device driver that can be used to support the LIM EMS 4.0 in the same manner as a standard LIM EMS card. The device driver is loaded at boot time and is a stay resident program. To install The device driver, a command line : DEVICE=EMMSAT.SYS Px Sz R nnnnn must appear in the CONFIG.SYS file. Where Px, Sz, R and nnnnn are optional parameters in the command line. Sx, Px, R and nnnnn represent the starting segment address parameter, the page mapping register, the expanded memory parameter and the shadow RAM switch respectively. If these parameters are absent, the default values will be used. To set the values other than the default values, the interpretation of the symbols is: P = I/O address to enable EMM pages x = 0 --> Y208h (default) = 1 --> Y218h = 2 --> Y258h = 3 --> Y268h = 4 --> Y2A8h = 5