2 2 1 7 A V D MICROPOLIS NO MORE PRODUCED Native| Translation ------+-----+-----+----- Form 3.5"/HH Cylinders 2360| | | Capacity form/unform 1700/ 2044 MB Heads 15| | | Seek time / track 10.0/ 1.5 ms Sector/track | | | Controller SCSI2 DI/FAST/AV Precompensation Cache/Buffer 512 KB WRITE/PARITY Landing Zone Data transfer rate 4.000 MB/S int Bytes/Sector 512 10.000 MB/S ext SYNC Recording method RLL operating | non-operating -------------+-------------- Supply voltage 5/12 V Temperature *C 5 50 | -40 65 Power: sleep W Humidity % 10 90 | 10 95 standby W Altitude km -0.061 3.048| -0.305 15.240 idle W Shock g 5 | 60 seek 12.2 W Rotation RPM 5400 read/write W Acoustic dBA 37 spin-up W ECC Bit 64 MTBF h 300000 Warranty Month Lift/Lock/Park YES Certificates ********************************************************************** L A Y O U T ********************************************************************** MICROPL. 2217/2210/2207/2205-D PRODUCT DESCRIPTION 135861 REV. A +---------------------------------------------------------+ | Differential +W1 |XX | ++ |XX | W2++J2 |XX ++ ++|| |XX ++ +W3 LED Option ++ |XX J1 |++++ W4+ |XX |+J9 Remote LED ID0+-+ ++ |XX | ID1| | |XX | ID2| | |XX | PT1| | |XX | WP | | |XX | SP0| | |XX | SP1+-+ | 1 | | | | | +-------+ |XX J3 | +++++++++ |XX Power +---------------------------------------------------------+ 1 Connector J2 (detail) --------------------- Pin 1 Slave Sync; 2 Not Connected; 3 Master Sync; 4 Ground; ++-+-+------------------------- || +-J4 Frame Ground Connector || || +----------+ || | ++++++++ J2 ||++-+1+2+3+4-+------------- ||| o o o o o o o o o o o o ||| o o o o o o o o o o o ||+---------J1----------- || +----------------- |+----+ +--------------------- ********************************************************************** J U M P E R S ********************************************************************** MICROPL. 2217/2210/2207/2205-D PRODUCT DESCRIPTION 135861 REV. A Jumper Setting ============== SCSI ID ------- +----------+-----------------------+ | SCSI ID | Jumpers | | | ID2 | ID1 | ID0 | +----------+-------+-------+-------+ | 0 | OPEN | OPEN | OPEN | +----------+-------+-------+-------+ | 1 | OPEN | OPEN | CLOSED| +----------+-------+-------+-------+ | 2 | OPEN | CLOSED| OPEN | +----------+-------+-------+-------+ | 3 | OPEN | CLOSED| CLOSED| +----------+-------+-------+-------+ | 4 | CLOSED| OPEN | OPEN | +----------+-------+-------+-------+ | 5 | CLOSED| OPEN | CLOSED| +----------+-------+-------+-------+ | 6 | CLOSED| CLOSED| OPEN | +----------+-------+-------+-------+ | 7 | CLOSED| CLOSED| CLOSED| (default) +----------+-------+-------+-------+ Up to eigth devices (the host and seven targets) can be attached to the SCSI Bus. The 2217D, 2210D, 2207D, and 2205D have three ID jumpers ID0, ID1, and ID2. The jumpers are used to assign one of eight SCSI ID bits (0-7) to the drive. In multiple-device systems, each drive must have its own unique ID. Interface Termination --------------------- EXTERNAL terminator only. The interface terminator provides proper termination for the inter- face lines and must be installed on the last device on the interface. For the differential drives, Micropolis recommends the use of an IN LINE TERMINATOR. The IN LINE TERMINATOR may be installed between the drive connector and the ribbon cable (Option 1), or the IN LINE TERMINATOR may be installed in the last plug on the ribbon cable (Option 2) . Option 1 -------- +-----------------------------------+ IN LINE | | TERMINATOR | 2217/2210/2207/2205-D +---+ ++-+ | | XX<- +--++-+<- +---+ To Host +-------------------------------+ J1 +--++-+ +-+-+ ++ |Cable Option 2 -------- ++ +-----------------------------------+ IN LINE ---+--++-+<-+---+ | | TERMINATOR +--++-+ +-+-+ | 2217/2210/2207/2205-D +---+ ++ | | | XX<- +---+ +-------------------------------+ J1 +-+-+ | To +------------------+ Host W1/W2 Spindle Sync Termination ------------------------------- W1/W2 CLOSED Slave Sync (W1) and Master Sync (W2) are terminated. (default) OPEN Spindle Sync is not terminated. Spindle Sync termination depends on system configuration; i.e. Master Mode or Master Controller Mode. W3 Remote LED Option --------------------- W3 CLOSED LED on Device Electronics board is enabled. (default) OPEN LED (user supplied) at J9 is enabled. W4 +5V to Bus Option --------------------- W4 CLOSED Drive provides terminator power. (default) OPEN Host system provides terminator power. SP0/SP1 Spindle Control Option ------------------------------- SP0 CLOSED SP1 OPEN Spindle motor starts when START UNIT command is received. OPEN Spindle motor starts at power-on. (default) SP0/SP1 Spindle Delay Option ----------------------------- SP1 CLOSED SP0 OPEN Spindle start-up is delayed based on SCSI ID (12 seconds per ID). OPEN Spindle start-up delay is disabled. (default) WP Write Protect Option ------------------------ WP CLOSED Drive is write protected. OPEN Drive is not write protected. (default) PT1 Bus Parity Check Option ---------------------------- PT1 CLOSED Drive neither generates nor detects parity. OPEN Drive generates parity and has parity detection enabled. (default) J3 DC Power and pin connector assignments ------------------------------------------- -------------------+ --+ +-----J3-----+| pin 1 +12 VDC 1| | 4 3 2 1 || pin 2 +12 Volts Return -+ +------------+| pin 3 + 5 Volts Return ------------------+ pin 4 + 5 VDC ********************************************************************** I N S T A L L ********************************************************************** MICROPL. 2217/2210/2207/2205-D/S PRODUCT DESCRIPTION 135861 REV. A Notes on Installation ===================== Recommended mounting orientations --------------------------------- horizontally vertically +-----------------+ +--+ +--+ | | | +-----+ +-----+ | | | | | | | | | +-+-----------------+-+ | | | | | | +---------------------+ | | | | | | | | | | | | | | | | | | | +-----+ +-----+ | +--+ +--+ The drives use industry-standard mounting for 3 -inch full-height Winchester disk drives. The drives are designed such that the outer frame should be hard- mounted to th ehost equipment; no additional/external shock mounts should be used. Recommend orientation is vertical on either side, or horizontal with the Device Electronics board down; other mounting orientations may be used. No matter what mounting orientation is used, Micropolis specifies that the maximum HDA casting temperature not exceed 60*C (140*F). If the HDA casting temperature measurement cannot be made, the ambient air temperature around the drive must be kept at or below 50*C (122*F). Caution: The mounting screws must be selected so that they do not penetrate the bottom mounting holes by more than 0.20 inches or the side mount- ing holes by more than 0.156 inches. Screws that are too long will short to PCBA components and/or prevent proper operation of the shock mount system. Mounting holes -------------- 3 per side and 4 on bottom #6-32 UNC-2B thru. Multiple-Drive Systems ---------------------- Drive #1 +------HOST------+ +-----------------+ | +-----------+ +--+-SCSI-BUS-----+ J1 | | |Terminators| | | +------+ J3 J4 | | +-----------+ | | | +--------+--------+ | | | | +------------------+ +----------------+ | | Drive #2 | | | +-----------------+ | +-------+------+ J1 | | | o------+ J3 J4 | | | | +--------+--------+ | | | +------------------o | | Drive #3 | | | +-----------------+ | +-------+------+ J1 | | | o------+ J3 J4 | | | | +--------+--------+ | | | +------------------o | | Drive #4 | | | +--------------+--+ | +-------+------+ J1 |T | | o------+ J3 J4 +--+ | ---DC-VOLTAGES-----+ +--------+--------+ | ---GROUND--------------------------o------------------+ T = TERMINATORS Terminators are installed ONLY in the last physical drive in the control chain. Connection J4 is provided for grounding; system characteristics determine the proper ground connection. J1 Signal Connector ------------------- Recommended Cable: 3M Scotchflex 3365/50 or equivalent Mating connector: 3M P/N 3425-3000 or equivalent J2 Spindle Synchronization connector ------------------------------------ Recommended mating connector: MOLEX 10-11-2043 or equivalent Pins: MOLEX 08-50-0005 Suggested wire size: 22-24 AWG for all pins J3 Power Connector ------------------ Recommended mating connector: AMP 1-480424-0 or equivalent Pins: AMP 350078-4 Suggested wire size: 18 AWG (minimum) for all pins. J4 Ground Connector ------------------- 3/16-inch spade lug J4 is provided for grounding. System character- istics determine proper ground connection. Recommended mating connector: AMP 60972-2 or equivalent J7 Remote LED Connector ----------------------- Recommended mating connector: Dupont 69305-002 or equivalent Pins: Dupont 77138-001 Suggested wire size: 26-30 AWG for all pins Differential Terminator ----------------------- Suggested Terminator: Methode DM 103-01-0 or equivalent SINGLE-ENDED Interface Electrical Characteristics ------------------------------------------------- Interface control and status signals are digital (open collector TTL) using industry-standard transmitters and receivers which provide a terminated, single-ended system. For active termination, the assigned signals are terminated with 110 ohms to +2.85V (nominal). For passive termination, the assigned signals are terminated with 220 ohms to +5V (nominal) and 330 ohms to ground. All signals use open-collector or three-state drivers. Single-ended drivers and receivers allow a maximum cable length of six meters (primarily for connection within a cabinet). Signal transmission requires a single 50-conductor (flat or twisted pair) cable. A characteristic impedance of 100 ( 10%) ohms is recommended. a. Input Characteristics Each of the drive's signal receivers has the following characteristics when measured at the interface connector. 1) Low-level input voltage (Signal true) = 0.0 VDC to 0.8 VDC 2) High-level input voltage (Signal false) = 2.0 VDC to 5.25 VDC 3) Low-level input current = -0.4 milliamps at 0.5 VDC 4) High-level input current = 0.1 milliamps at 2.7 VDC 5) Minimum input hysteresis = 0.2 VDC 6) Maximum input capacitance = 25 pF b. Output Characteristics Each of the drive's signal drivers has the following characteristics when measured at the interface connector. 1) Low-level input coltage (Signal assertion) = 0.0 VDC to 0.5 VDC 2) High-level input voltage (Signal negation) = 2.5 VDC to 5.25 VDC 3) Minimum driver output capability = 48 milliamps (sinking) at 0.5 VDC. c. Terminator Power (TERMPWR at Pin 26) Terminator Power has the following requirements: V(TERM) = 4.25 VDC to 5.25 VDC 800 milliamps minimum source drive capability, with 1.0 amp recommended current limiting (e.g., a fuse). 1.0-milliamp maximum bus loading (except for the purposes of providing power to an internal terminator). The drive provides keyed connectors to prevent accidental grounding or misconnection of terminator power. DIFFERENTIAL Interface Electrical Characteristics ------------------------------------------------- Differential interface signals consist of two signal lines which are denoted +SIGNAL and -SIGNAL. A signal is defined as true when the +SIGNAL is more positive than the -SIGNAL. A signal is defined as false when the -SIGNAL is more positive than the +SIGNAL. Differential drivers and receivers allow a maximum cable length of 25 meters. Signal transmission requires a single 50-conductor cable. A characteristic impedance of 100 ( 10%) ohms is recommended for un- shielded flat or twisted pair ribbon cable. A minimum conductor size of 28 AWG should be employed to minimize noise effects and ensure proper distribution of optional terminator power. A stub length of no more than 0.2 meters is allowed off the main-line interconnection within any connected equipment. a. Input Characteristics Each of the drive's signal receivers has the following characteristics when measured at the interface connector. I (input current on either input) = 2.0 milliamps, maximum Note: These characteristics include both receivers and passive drivers. This requirement is met with the input voltage varying between -7V and +12V, with power either on or off, and with hysteresis equaling 35 millivolts, minimum. b. Output Characteristics Each driven signal has the following characteristics when measured at the interface connector. VOL (low-level output voltage) = 1.7V maximum at IOL where IOL = 55 milliamps VOH (high-level output voltage) = 2.7V maximum at IOH where IOH = -55 milliamps VOD (differential voltage) = 1.0V minimum, with common-mode voltage ranges from -7 to +12 VOL and VOH are measured between the output terminal and the SCSI device's logic ground reference. c. Terminator Power (TERMPWR at Pins 25 and 26) Terminator Power has the following requirements: V(TERM) = 4.0 VDC to 5.25 VDC 600 milliamps minimum source drive capability, with 1.0 amp recommended current limiting (e.g., a fuse). 1.0-milliamp maximum bus loading (except for the purposes of providing power to an internal terminator). The drive provides keyed connectors to prevent accidental grounding or misconnection of terminator power. Adjustments and Maintenance --------------------------- The drives requires no adjustments or periodic maintenance; additionally, no mechanical adjustments are required to prepare a system for handling or shipment. Field-Replacable Components --------------------------- The concept of repair by replacement of complete functional components is utilized in the drive, resulting in an MTTR of less than 15 minutes. Data Transfers -------------- The drives are capable of transferring data up to 10 MBytes/sec in synchronous mode and 5 MBytes/sec in asynchronous mode. ********************************************************************** F E A T U R E S ********************************************************************** MICROPL. 2217/2210/2207/2205-S/D PRODUCT DESCRIPTION 135861 REV. A The single-ended and differential interface drive is compatible with the "ANSI CCS" and "SCSI-2" versions of the industry-standard Small Computer System Interface (SCSI) specification. Media Defects ------------- Media defects are physical characteristics of the media which result in repetitive read errors when a functional drive is operated within specified operating conditions. At the time of manufacture, a media test system evaluates every drive and identifies each media defect location. The defective areas are identified by head address (HD), cylinder address (CYL), and number of clocks from Index (CFI). The list of manufacturer-found defects is stored on the drive in a reserved, write-protected area accessible by the SCSI controller. This list is known as the MDL (Manufacturers Defect List) or PList (Primary Defect List). A printed listing of the defects is also shipped with each drive. The entries it contains can be mapped out (reassigned) automatically at format control parameter bits. Seek Time --------- ----------------------------------+--------+ Track-to-Track read msec. typ. | 1.5 | write msec. typ. | 2.5 | Average msec. typ. | 10 | msec. max. | 25 | Latency msec. avg. | 5.56 | ----------------------------------+--------+ Multi-Segment Read Ahead ------------------------ The Multi-Segment Read Ahead function partitions the 256K data buffer into multiple buffers or segments. The read-ahead function causes the drive to transfer the requested block into its buffer and continue to read sequential blocks until the buffer (or segment) is filled or another command is received. On subsequent request data, the buffer will be checked for the requested blocks. If the data already resides in the buffer, it will be transferred to the host and no media access will be necessary. This results in a significant improvement in performance. Internal Data Rate ------------------ 32 to 46 MHz Sector Size = Variable; programmable up to 4096 bytes. ********************************************************************** G E N E R A L ********************************************************************** MICROPOL. AV LT What is an AV Drive? -------------------- Today's demanding digital video and audio applications require disk drives to sustain a pre-determined minimum data transfer rate. Any interruptions in this data rate are detrimental to AV applications that require constant delivery of data at 30 frames per second minimum. In standard drives utilized for data processing requirements, the error correction and thermal calibration methods employed are not optimized for continuous delivery of data. These routine housekeeping tasks will procedure gaps in the data stream as long as 850 ms, resulting in jumps, gaps, and stutters in motion and sound when used in most AV applications. (MICROPOLIS 10/96) Installation Guide for IBM PC & Compatible ========================================== Daisy Chain Option Kit ---------------------- The MICRODISK AV LT subsystem will normally be last SCSI device on the daisy chain. However, if you wish to daisy chain your MICRODISK AV LT subsystem to other SCSI devices, you will need one Daisy Chain Option Kit. This kit includes one each of the following items: - SCSI System Cable (right angle connector) - Daisy Chain (DCO) SCSI Backplane Cable - MHA Rear Cover Two SCSI system cables are available. Both cables have a Centronics 50-pin connector at the MICRODISK AV LT end, and either a Centronics 50-pin or mini-SCSI connector at the other end. NOTE Connect the SCSI system cable's right angle connector to the back of the module. Using the Daisy Chain Option Kit -------------------------------- The MICRODISK AV LT subsystem will normally be the last SCSI device on the daisy chain. However, if you wish to daisy chain your MICRO- DISK AV LT subsystem to other SCSI devices, you will need one Daisy Chain Option Kit. To allow your MICRODISK AV LT subsystem to daisy chain to other SCSI devices, you will remove the SCSI Backplane Cable from a MICRODISK AV LT module (usually the TOP module in the stack), and replace it with a Daisy Chain SCSI Backplane Cable. You will then install the MHA rear cover, and connect the rightangle connector end of the SCSI system cable to the Daisy Chain SCSI Backplane Cable connector, and the other end (50-pin Centronics connector) to another SCSI device outside the MICRODISK AV LT subsystem. Installation Guide for IBM PC & Compatible ========================================== Cables/Cords ------------ MICRODISK AV LT SCSI cables and AC power cords are manufactured to the industry standard for this type of application. MICRODISK AV LT module interconnect cables and cords have specific design features to maintain both aesthetics and uncompromising performance. Failure of any single power cord or SCSI cable will not cause data to be lost. Failure of a single cord or cable may sometimes cause all disk drive access to cease, but should never cause data stored on a MICRODISK AV LT drive to be lost. Getting Started --------------- There are several kits that may be shipped for assembly and installa- tion of a MICRODISK AV LT subsystem. The minimum MICRODISK AV LT subsystem requires at least: - One MICRODISK AV LT Module Kit. - One MICRODISK AV LT System Configuration Kit. - One SCSI/Power Cable Kit. - One SCSI host adapter. Depending on the configuration you may also need: - Additional SCSI host adapters. - One or more MICRODISK AV LT Module Kit(s). - One or Expansion Kit(s). - One or more MICRODISK AV LT Multiple Host Adapter (MHA) Option Kit(s) . - One or more MICRODISK AV LT Daisy Chain Option Kit(s). CAUTION Do not twist cable or cord connectors during unpacking or assembly; damage may occur. MICRODISK AV LT Module Kit -------------------------- A MICRODISK AV LT Module Kit includes one each of the following items: - MICRODISK AV LT Module - Front Cover - Rear Cover - Hardware Registration Card - Read First Document To increase available storage capacity, modules may be assembled in a "stack". If you use more than nine modules in your MICRODISK AV LT subsystem, new stacks should be created to accommodate the additional modules. NOTE The maximum recommended number of modules in each stack is nine. Only seven SCSI devices can be connected to a single host adapter If you have more than seven modules in your stack, you must install a second host adapter and use a Multiple Host Adapter (MHA) Option Kit. If you create more than one stack, you will need one Expansion Kit and one SCSI/Power Cable Kit for each additional stack you create. System Configuration Kit ------------------------ MICRODISK AV LT subsystems are assembled with the components included in the MICRODISK AV LT System Configuration Kit, Module Kit(s), and SCSI/Power Cable Kits. One System Configuration Kit is required per MICRODISK AV LT subsystem. The MICRODISK AV LT System Configuration Kit includes one each of the following items: - Top Cover - SCSI Terminator - Base Assembly (with Power Switch) - Read First Document - Assembly and Installation Guide. SCSI/Power Cable Kit -------------------- One SCSI/Power Cable Kit is needed per stack. There are six types of cable kits to address the Centronics SCSI Connector (ISA) or mini- SCSI Connector (EISA/MCA) and three types of AC Power Cords available: U.S., U.K., or European: - U.S. Standard SCSI/Power Cable Kit - U.S. Mini-SCSI/Power Cable Kit - U.K. Standard SCSI/Power Cable Kit - U.K. Mini-SCSI/Power Cable Kit - European Standard SCSI/Power Cable Kit - European Mini-SCSI/Power Cable Kit Each type of SCSI/Power Cable Kit includes one each of the following items: - SCSI System Cable (Centronics SCSI) - AC Power Cord Expansion Kit ------------- One Expansion Kit is necessary for every new stack you create. An Expansion Kit includes one each of the following items: - Top Cover - SCSI Terminator - Base Assembly (with Power Switch) Multiple Host Adapter Option Kit -------------------------------- One MHA Option Kit, required for each additional host adapter used in any single stack, includes one each of the following items: - SCSI System Cable (right angle connector) - MHA SCSI Backplane Cable - SCSI Terminator - MHA Rear Cover Two SCSI system cables are available. Both cables have a Centronics 50-pin connector at the MICRODISK AV LT end, and either a Centronics 50-pin, mini-SCSI, or mini-SCSI connector at the host adapter end. NOTE Connect the SCSI system cable's right angle connector to the back of the module. Compatible SCSI Host Adapters ----------------------------- Your computer needs at least one SCSI host adapter in order to communicate with modules in a MICRODISK AV LT subsystem. If you need a SCSI host adapter or have any questions, please contact your dealer. The following is a table showing the recommended MICRODISK AV LT compatible SCSI host adapters: +----------------+--------------------------------------+ | | Architecture | |Company | ISA | EISA | MCA | +----------------+--------------+-------------+---------+ |ADAPTEC |AHA1540B/42B |AHA1740/42A* |AHA1640* | | |AHA1540C/42C | | | +----------------+--------------+-------------+---------+ |ALWAYS TECH. |IN2000* | | | +----------------+--------------+-------------+---------+ |BUSTEK/BUSLOGIC |BT540/42 |BT740/42* | | +----------------+--------------+-------------+---------+ |DPT |PM2011 |PM2012B/90 | | | | |PM2012B/95 | | +----------------+--------------+-------------+---------+ |DTC |DTC3180A/3280A|DTC3190 | | | | |DTC3290 | | +----------------+--------------+-------------+---------+ |FUTURE DOMAIN |TMC1660* | | | | |TMC1670* | | | | |TMC1680* | | | +----------------+--------------+-------------+---------+ |MYLEX | |DCE376* | | +----------------+--------------+-------------+---------+ |ULTRASTOR |ULTRA14F* |ULTRA24F* | | +----------------+--------------+-------------+---------+ * These host adapters do not accept the standard 50-pin SCSI connector cable. Please contact your reseller to obtain the appropriate cable if you have one of these host adapters. Host Adapter Considerations --------------------------- - One MHA Option Kit is required for each additional host adapter you add to an existing stack. - When installing host adapters, ensure that there are no port address or IRQ conflicts with other cards already installed or planned for installation. Refer to your host adapter documentation for specific details. MICRODISK AV LT Assembly ------------------------ A MICRODISK AV LT subsystem may be as small as one module, or you can add modules to increase storage capacity and create multiple stacks if you so desire. The minimum MICRODISK AV LT configuration requires on MICRODISK AV LT Module Kit, one System Configuration Kit, one SCSI cable, one power cord, and one SCSI host adapter. Terminator ---------- The terminator must installed in the last module in the chain for each SCSI bus (Host Adapter). MICRODISK AV LT Series Disk Drives ---------------------------------- Each module in a MICRODISK AV LT subsystem contains a MICRODISK AV LT Series disk drive. MICRODISK AV LT Series disk drives are engineered specifically for multimediam high-end graphics, and digital audio/ video applications. MICRODISK AV LT Series disk drives have the highest minimum sustained data rate in the industry in their class at 3.0 MB/sec, and a maximum sustained uninterrupted data rate of 2.9 MB/sec. Industry standard high capacity data processing drives are not designed for high sustained, uninterrupted data rates - factors which are required for real-time recording and playback of digital audio/video data. Standard drives perform short, random "burst" transfers, leaving gaps in the data stream. MICRODISK AV LT Formatting/Partitioning --------------------------------------- Your MICRODISK AV LT subsystem modules need to be formatted and partitioned before they can be used for data storage. To perform these functions, use the disk formatting/partitioning utility program(s) that you received as part of your operating system software. The utilities prepare your MICRODISK AV LT modules for use. Under normal circumstances you will only need to format and partition each MICRODISK AV LT module once. NOTE Because each module in a MICRODISK AV LT stack is a separate, independent SCSI device, you must format and partition each MICRODISK AV LT module separately. Formatting the Hard Disk ------------------------ Formatting lays down distinct patterns on the disk which set up the disk's organizational structure. You normally need to format the disk only once. Installing Partitions --------------------- Partitioning prepares a hard disk for use by the PC. Partitions allow you to divide the space available on the hard disk into separate areas which appear on the desktop as separate logical disk drives (volumes). This allows more flexible management of files (i.e., you can use one partition for word processing, another for database work, etc.). Management of back-up also becomes easier with a wellorganized and partitioned hard disk. A large hard disk with many small files takes up a lot of disk space because of the way the filing system allocates disk space. You can save space by partitioning the hard disk into smaller volumes. Carefully plan your partitions, as you cannot change partitions with- out erasing your data. If you choose to alter the sizes or types of partitions, you should: 1. Back up all your files 2. Make partitioning changes 3. Restore the files to their new volumes. CAUTION Remember, you can change partitions later, but all the information stored on them will be lost. Make sure you have all data from these partitions backed-up before changing the partitions. It is not necessary to reformat the disk to redefine the partitions. MICRODISK AV LT Operation ------------------------- The MICRODISK AV LT subsystem MUST be turned on prior to, or at the same time as, your computer. The MICRODISK AV LT subsystem MUST be turned on whenever your computer is on.