WESTERN DIGITAL COMPUTER SYSTEM MAPS FOR HELP IN CONFIGURING "PLUS" (WD8003 and WD8013) FAMILY LAN ADAPTERS --------------------------------------------------------------------- Copyright Western Digital Corporation 1988, 89, 90. All Rights Reserved. The Western Digital PLUS family LAN adapters use three resources to communicate with the computer system. These are the IRQ (interrupt), I/O Base Address, and RAM buffer area. The LAN adapter board does not have the capability to share these resources. This means that problems can occur if you try to share these areas with other add-on boards or other parts of the computer that use these resources. Below is a description of the three resources and what common devices use them. Use this as a guide when installing a Western Digital LAN adapter. You should not change the factory setting of the LAN adapter if there are no conflicts with it. If necessary, it is a simple matter to change to a different configuration. The factory settings are: IRQ = 3; I/O Base Address = 280 (hex); RAM Buffer Base Address = D0000 (hex). Note that the RAM Buffer location is determined by the software driver(s) you use, not by jumpers or other settings on the board itself. ===================================================================== SYSTEM RESOURCES USED BY LAN ADAPTER BOARDS ===================================================================== (1) IRQ - Interrupt Request Channel Use the chart below to determine which interrupt is best for the LAN adapter board. If you cannot find any available interrupt, you then need to remove or disable something from the system. Most Western Digital adapters for XT/AT bus systems can select interrupt 2, 3, 4, 5, 6, or 7. Micro Channel bus adapters can select interrupt 3, 4, 10, or 15. Please refer to the User Installation Guide that comes with the adapter to determine which interrupts your LAN adapter can select. Interrupt Other Devices That This IRQ May Not Be Available (IRQ) Use This IRQ For LAN Adapter If ... --------------------------------------------------------------------- | 2 | (Usually available) | if EGA or VGA installed | | 3* | COM2:, SDLC, BSC | if 2nd SERIAL PORT installed | | 4 | COM1:, SDLC, BSC | if 1st SERIAL PORT installed | | 5 | Hard Disk (in XTs) | in an XT with a hard disk --or-- | | | LPT2: (in ATs) | an AT with a 2nd PARALLEL PORT | | 6 | Floppy Disk | in any system with a floppy drive| | 7 | LPT1: | if 1st PARALLEL PORT installed | |-------------------------------------------------------------------| | IRQ's 2 through 7 are only on XT computer systems and IRQ's | | 2 through 15 are only on AT computer systems. | |-------------------------------------------------------------------| | 8 | Realtime Clock IRQ | used by computer system | | 9 | INT 0Ah (IRQ 2) | Software Redirected to IRQ 2 | | 10 | (Usually available) | if other device occupys irq 10 | | 11 | (Usually available) | if other device occupys irq 11 | | 12 | (Usually available) | if other device occupys irq 12 | | 13 | used by system | is the Coprocessor irq | | 14 | used by system | Fixed Disk Controller | | 15 | (Usually available) | if other device occupys irq 15 | --------------------------------------------------------------------- * Factory setting ===================================================================== (2) I/O Base Address This is a special area in memory used by the computer system to communicate with devices external to the microprocessor. These addresses are always stated in hexadecimal (hex). Western Digital LAN adapter boards use 32 decimal (20 hex) consecutive I/O addresses starting at any base address between 200 and 3E0. If the factory setting of 280 is selected, for example, the adapter will use addresses 280-29F. Below is a map of common devices and the I/O ports that they use. The numbers in the left column are the possible selections for the LAN adapter I/O Base Address. If there is something using an address (for example, if you have a game controller at address 200), then do not locate the LAN adapter at that address. Any address can be used as long as something else in the system is not trying to use the area between that base address and the next one. Possible I/O Potential Conflicting Devices And Their Base Addresses Typical I/O Addresses --------------------------------------------------------------------- | [200] | Game Controller/Joystick (200 - 20F) | | | Expansion Unit (210 - 217) | | [220] | Novell NetWare Key Card | | [240] | | | [260] | LPT2: (278 - 27F) | | [280]* | LCD display on Wyse 2108 PC | | [2A0] | | | [2C0] | | | [2E0] | COM4: (2E8 - 2EF) GPIB-Adapter 0 (2E1) | | | COM2: (2F8 - 2FF) Data Acquisition (2E2 - 2E3) | | [300] | Prototype Card (300 - 31F) | | | 3Com EtherLink factory setting is 300 - 31F | | [320] | XT Hard Disk Interface (320 - 32F) | | [340] | | | [360] | LPT1: (378 - 37F) | | [380] | SLDC/Secondary Bi-sync Interface (380 - 38C) | | [3A0] | Primary Bi-sync Interface (3A0 - 3A9) | | | Monochrome Display (3B0 - 3BB) | | [3C0] | EGA Display Control (3C0 - 3CF) | | | Color/Graphics Display-CGA (3D0 - 3DF) | | [3E0] | COM3: (3E8 - 3EF) | | | Floppy Disk Controller (3F0 - 3F7) | | | COM1: (3F8 - 3FF) | --------------------------------------------------------------------- * Factory setting Any addresses without a description are usually available for use. Note that computers that have a small built-in LED or LCD display (to show disk cylinder data or clock speed, for example) might use certain I/O addresses to interface with that display. ===================================================================== (3) RAM Buffer - Shared Memory Base Address RAM buffer memory that resides on Western Digital LAN adapter boards is used for passing data to and from the adapter. You must select an area in your system's memory space above the DOS 640K boundary where this buffer can reside without conflicting with RAM or BIOS ROMs located on other add-on boards in your system. The RAM buffer on a Western Digital LAN adapter can occupy a space of 8, 16 or 32 Kbytes depending on the type of adapter: When using a board with a ROM installed, space must be allocated for both the RAM buffer and the ROM. Just as with other devices, the RAM and ROM areas must not conflict with each other. ROM sizes can be 16, 32, or 64 Kbytes. The memory locations for the RAM Buffer are always expressed in hexadecimal. 640K in hexadecimal is A0000. This is the first available location for the RAM Buffer. Using a base address of D0000 (the default for most Western Digital software drivers) as an example, here are the ranges of memory occupied by the LAN adapter RAM buffer: 8 Kbytes - Would use D0000 through D1FFF 16 Kbytes - Would use D0000 through D3FFF 32 Kbytes - Would use D0000 through D7FFF Below is a map of how the memory space above 640K (A0000) is used on many computer systems. Use this as a guide to determine where to locate the RAM (or ROM) on the LAN adapter. Remember that the RAM Buffer location is determined by the software driver(s) you use, not by jumpers or other settings on the board itself. Possible Memory Spaces Devices That Use Portions See For RAM Buffer Of This Memory Space Note -------------------------------------------------------------- | A0000-AFFFF (Page A) | EGA on-board video memory | 1 | | B0000-B7FFF (Page B0) | Mono on-board video memory | 1 | | B8000-BFFFF (Page B8) | RGB and mono video memory | 1 | | C0000-C7FFF (Page C0) | EGA BIOS ROM | 1 | | C8000-CFFFF (Page C8) | XT hard disk BIOS ROM | 1 | | D0000-DFFFF (Page D) | Expansion RAM (LIM) area | 2 | | E0000-EFFFF (Page E) | Expansion RAM area and some | 2 | | | AT system ROM BIOS | | | F0000-FFFFF (Page F) | Permanent system ROM BIOS area | | -------------------------------------------------------------- Note 1: Portions of this memory area are also used by VGA video boards, but there is considerable variation depending on the manufacturer. We recommend setting the RAM Buffer Address to D0000 or above if an 8-bit VGA is installed. If you have a 16-bit VGA installed, there are two options. The first option is to convert the 16-bit VGA to 8-bit mode operation and use the RAM Buffer address of D0000. The second option is for 16-bit VGA mode operation. This option is only operational if the computer system does not occupy E0000. Set the RAM Buffer address using Nwpatch to E0000. If EGA is installed use the factory setting of D0000. Note 2: Portions of this memory area are used by most memory expansion boards for page swapping. This memory area is also occupy by 16-bit VGA video board, please read note 1.