Chips and Technologies DS82C235 SCATEMM.SYS EMM Driver Documentation I. Introduction: This document describes the MS-DOS device driver SCATEMM.SYS, which in conjunction with a Chips and Technologies 82C235 "SCAT" chip or 82C236 "SCATsx" chip provides support for LIM EMS 4.0 II. Device Driver Installation This EMS driver is supplied as a device driver that can be loaded at DOS boot time. The user is required to edit the CONFIG.SYS file so that it contains a line in the form of: DEVICE = d:[path]\SCATEMM.SYS [options] where d: and [path] represent the drive and path where the driver is located. The driver is designed so that, under normal circumstances, it does not need any command line options in order to give satisfactory performance. However, command line options are provided so that the driver may be tailored to a user's specific needs. Before installing the driver, you should run your system SETUP and make sure to set aside sufficient memory for your needs. This memory should be designated as expanded memory. III. Command Line Parameters The following command line parameters are available for knowledgeable users who wish to tailor the driver for their own requirements. Option names may be shortened to their first two characters. Options should be separated by one or more spaces. Spaces are optional before and after the '-' and '=' symbols. FRAME = aaaa Specifies the page frame address (the address of the 64K segment through which expanded memory is mapped. "aaaa" must be either D000 or E000. Specifying FRAME will override the automatic choice of page frame by the driver. EXCLUDE = xxxx [- cccc] Specifies an area of memory which should not be under the control of the SCATEMM.SYS driver. "xxxx" and "cccc" specify the address or range of addresses of memory to be excluded and should be in multiples of 16K (i.e. end in 00). EXCLUDE may be used several times on the driver command line to exclude multiple blocks of memory, though at least 64K of memory should remain above 640K (A000). The driver will find all RAM/ROM in the range D000 - EFFF, and will adjust for them. INCLUDE = xxxx [- cccc] Specifies memory to be included under the control of the SCATEMM.SYS driver. Parameters are similar to EXCLUDE above. HANDLES = hhh Specifies the number of handles and names available. "hhh" must be in the range of 16 to 255, with the default being 64. IOADDR = aaa Overrides the default base I/O address at which the "SCAT/SCATsx" Chip should be configured. aaa must be either 208 or 218. DIAGS = xxx Specifies whether EMS memory diagnostics are performed during initialization of the driver. "xxx" must be ON or OFF. The default is OFF. IV. Error Messages "Initialization Error. Memory Manager not Installed" This is a generic error message that is accompanied by another error message. This means that for some reason (given by the other error message) the EMM driver could not be installed correctly. "Cannot detect mapping hardware" The EMM driver could not find a Chips 82C235 "SCAT" chip or 82C236 "SCATsx" chip in the system. Make sure that your EMS is enabled. This error may indicate that you have the wrong driver for your system. "Problems encountered with memory initialization" The EMM driver could not set up the page frame correctly. Make sure that there is at least one contiguous 64K segment of unused memory space above 640K (A000). "Interrupt 67 Vector already allocated" Some other driver has already allocated the EMS interrupt vector. Remove all other EMS drivers from your CONFIG.SYS file. "I/O address specified is not one of the permitted values" The EMS mapper I/O address you indicated using the IOADDR command line option is an invalid address. Make sure that it is either 208 or 218. "An equals (=) sign was expected" One of your SCATEMM.SYS command line options was not immediately followed by an equals '=' sign. Check your CONFIG.SYS file to make sure the SCATEMM.SYS command line is formatted correctly. "Invalid HEX number or not divisible by 16" One of your INCLUDE or EXCLUDE "xxxx" command line arguments is incorrect. Each "xxxx" argument for these options must be divisible by 16 (ending in 00). "Number of handles invalid or out range" The value you specified for the HANDLES command line option is invalid. Make sure it is a decimal number between 16 and 255. "Invalid Page Frame Address" The page frame address you specified is invalid. The page frame must start at either D000 or E000. "No working memory can be found. EMM aborted" The driver cannot find any memory set aside as expanded memory. Make sure to run your system SETUP, and set aside some memory for expanded memory. "Unrecognized command/option in command line" The string displayed after this error message was found to be invalid. Edit your CONFIG.SYS to make sure this invalid option is corrected. "End address is less than starting address" One of the "cccc" addresses specified for either the INCLUDE or EXCLUDE options is less than the "xxxx" value for that option. "The command line is incomplete" Options are incomplete on the SCATEMM.SYS command line. Make sure that all command line options are correctly formatted. "Problems encountered in setting default page frame address" The default page frame address found in your system CMOS is invalid. This is not a fatal error, if this occurs the driver will use the default base address. Make sure to run your system SETUP and make sure that your EMS base address is valid. "Decimal number input overflow error" The number of handles specified is an invalid number. Edit your CONFIG.SYS and make sure that the parameter for HANDLES is correctly formatted. "Error EMS I/O not enabled" EMS has not been enabled on the Chips 82C235 "SCAT" or 82C236 "SCATsx" ChipSet. Run your system SETUP and make sure EMS has been enabled. "The EMS hardware is disabled or not functional" This is a generic error message that is accompanied by another error message. This means that for some reason (given by the other error message) the EMS hardware is not operating properly.