S T 1 8 7 7 1 F C B A R R A C U D A 8 SEAGATE NO MORE PRODUCED Native| Translation ------+-----+-----+----- Form 3.5"/HH Cylinders 5333| | | Capacity form/unform 8700/10800 MB Heads 20| | | Seek time / track 9.0/ 0.8 ms Sector/track | | | Controller FIBRE CHANNEL DUAL Precompensation Cache/Buffer 2048 KB MULTI-SEGMEN Landing Zone Data transfer rate 12.000 MB/S int Bytes/Sector 512 100.000 MB/S ext SYNC Recording method PRML 0/6/6 operating | non-operating -------------+-------------- Supply voltage 5/12 V Temperature *C 5 50 | -40 70 Power: sleep W Humidity % | standby W Altitude km | idle 16.4 W Shock g | seek W Rotation RPM 7200 read/write W Acoustic dBA spin-up W ECC Bit MTBF h 1000000 Warranty Month 60 Lift/Lock/Park YES Certificates ********************************************************************** F E A T U R E S ********************************************************************** AMPEX PYXIS TECHNICAL MANUAL 3315507-01 REV. B, 8/83 General Description =================== The Pyxis Model 7/13/20/27 disk drives are fixed-media, random- access, rotating memory storage devices that enable the central processing unit (CPU) of a data processing system to store and re- trieve blocks (records) of data on rotating disks. The drive can operate as a single stand-alone input/output device for the CPU, or it can operate with other similar disk drives in a daisy-chain configuration. There are four disk drives (Models 7, 13, 20, and 27) in the Pyxis series containing 1, 2, 3 or 4 magnetic disks which range in total data storage from 6.7 megabytes to 26.67 megabytes, unformatted, and 5.24 megabytes to 20.97 megabytes, formatted. Access to data is provided by one moving head per disk durface. The heads are an integral part of the head disk assembly (HDA) and never require alignment in the field. Data is recorded on the disk surfaces using modified frequency modulation (MFM) techniques. Data access time ---------------- Average latency 8.3 ms Average data access time/ramp mode 98.3 ms Average data access time/3 milliseconds step mode 368.3 ms Head switching time 5 microsec. max. Illegal Address Map ------------------- An illegal address map supplied with each drive informs the user of areas of defects. A media defect is a physical characteristic of the media which results in a repetitive read error when a properly adjusted unit is operated within the specific operating conditions. Valid data must not be written over known media defects; therefore, sector/track deallocation or other known media defects must be utilized to avoid these areas. A label fixed to each drive indicates the addresses of sectors which should be ignored by the host. These sector addresses are identified by cylinder, head, and sector. No illegal addresses exist in cylinders 0, 1, and 2. The format used for this purpose is 33 sectors per track, each sector consisting of 256 bytes. Indicators ---------- When they are lit, the two red LEDs fixed to the master electronics board are visible through the facia. The Power On LED is located closest to the center of the facia and is on when the drive is Ready and no error is present. It is also used to indicate fault condi- tions in the drive. The Power On LED will not come on, indicating an error, if +5 volt supply does not come up and stabilize within one second. The Select LED comes on (provided the Power On LED is on) when the drive is ready and selected by the host. Power-Up Diagnostics -------------------- During the power-up sequence in the drive, a number of automatic diagnostic routine sequences are performed before the drive becomes ready for system usage. When a fault error occurs, an appropriate error code is displayed in the fault indicators. The Power On LED is used to flash error messages when fault conditions occur in the drive. A 4-bit binary code is used (long flash = logic 1 and short flash = logic 0) with the most significant bit occuring first. Power-Up Sequence Error Codes +-----------+-----------------------------------------------+ |Error Code |Error | +-----------+-----------------------------------------------+ | 1(0001) |No index track data burst at track-2 or track-3| +-----------+-----------------------------------------------+ | 2(0010) |No flag 0 from track 0 detector | +-----------+-----------------------------------------------+ | 3(0011) |Motor speed exceeds 1% tolerance | +-----------+-----------------------------------------------+ | 5(0101) |Flag 0 always true | +-----------+-----------------------------------------------+ | 9(1001) |Microprocessor self-test failed | +-----------+-----------------------------------------------+ | 10(1010) |No Index | +-----------+-----------------------------------------------+ | 11(1011) |Motor not up to speed | +-----------+-----------------------------------------------+ Operational Error Codes +-----------+------------------------------------------------------+ |Error Code |Error | +-----------+------------------------------------------------------+ | 4(0100) |Motor speed exceeds +10%, -5% tolerance during normal | | |operation. | +-----------+------------------------------------------------------+ | 6(0110) |Step pulse while Write Gate is true | +-----------+------------------------------------------------------+ | 7(0111) |Static Write Fault condition: | | +------------------------------------------------------+ | |1. Write current and no Write Gate, or | | +------------------------------------------------------+ | |2. No write current, no Write Gate, or | | +------------------------------------------------------+ | |3. More than one read/write head selected, or | | +------------------------------------------------------+ | |4. 12-volt supply below 10.3 volts, or | | +------------------------------------------------------+ | |5. 5-volt supply below 4.5 volts | +-----------+------------------------------------------------------+ Media Defects ------------- Model 7 = 2 Model 13 = 4 Model 20 = 6 Model 27 = 8 ********************************************************************** G E N E R A L ********************************************************************** SEAGATE FC-AL INTERFACE An Overview of Fibre Channel --------------------------- Introduction ------------ Everyone has accepted the fact that we have moved into the Age of Information. In this paradigm information itself is a commodity, and therefore there is great value in its efficient disbursement. Unfortunately, industry has placed greater value in creating information, than distributing it. We often hear about new machines which are capable of performing prodigious calculation at the blink of an eye. New reports of ever faster computers are commonplace. Sharing this information, however, has become a priority only recently. It seems that although we have moved into the Age of Information, one of our biggest challenges is to efficiently distribute the information for everyone to use. Luckily, a viable solution is at hand. Conceived and supported by such industry giants as IBM, Hewlett-Packard, and Sun Microsystems, the Fibre Channel is aimed at providing an inexpensive, flexible and very high-speed communications system. Most of the popular network implementations today can claim to have any two of these elements. Since Fibre Channel encompasses all three, it has everything necessary to become a resounding success. Not the Network Fibre Channel has significant advantages over common networks. The first difference is speed. The fastest network implementations today support transfer data at a little over 100 megabits per second. For smaller data files, where a single computer is directly communicating with a file server, such speeds are adequate. However, for realtime video and sound, or systems where two machines must operate on common data even 200 megabits per second is hopelessly inadequate. Fiber Channel provides significantly higher rates, from 10 to 250 times faster than a typical Local Area Network (LAN). In fact, Fibre Channel can transfer data at speeds exceeding 100 megabytes, or 800 megabits, per second. This speed is sufficient to allow transfer of a 1024x768 image with 24-bit color at 30 frame per second, and CD- quality digital sound. This overcomes the bandwidth limitation, which is probably the most serious impediment for LAN performance. As the number of computers communicating on a common network increases, the amount of data packets increases accordingly. This is because data on a LAN is common to all computers on that network. The software must decide if a particular message is relevant for a particular machine. When several machines are communicating with one another, every other machine on the network must contend with all of the messages. As the number of messages increases, the load for the entire system is increased. Fiber channel is a switched system. Much like a telephone system, a connection is established between only the parties that need to communicate. These parties can share the entire bandwidth of Fibre Channel, since they do not have to contend with messages not relevant to their communication. LANs attempt to compensate for this by increasing the transfer speed, which places an even greater burden on the software. Since all protocol for Fibre Channel is handled by the hardware, the software overhead is minimal. Fibre Channel also supports full parallelism, so if greater capacity is needed, more lines can be added. The common analogy for showing the advantages of parallelism is the effect of doubling the number of lanes on a freeway instead of doubling the speed limit. The physical distance between computers is another limiting factor for conventional LANs. Ethernet cables usually have a limit of 1000 feet between machines whereas Fibre Channel can support a link between two up to 10 kilometers apart. Finally, Fibre Channel is not software intensive. All of the essential functions are handled by hardware, freeing the computer's processor to attend to the application at hand. Even the error correction for transmitted data is handled by the Fibre Channel hardware. In standard LANs this requires precious processor resources. Advantages for Computing ------------------------ The obvious advantage for Fibre Channel is to facilitate communication between machines. Several workstations clustered together already surpass the speed and capacity of a VAX, and begin to rival the power of a super computer, at a much lower cost. The power of concurrent processing is awesome. For example, a single neuron inside our brain is much less complex, and operates far slower than a common 286 processor. However, millions of neurons working in parallel can process information much faster than any processor known today. Networking simple logical units, and operating them in parallel offers advantages simply unavailable for the fastest single processor architectures. These shared architectures require a huge amount of communication and data sharing which can only be handled by high-speed networks. Fibre Channel not only meets these requirements, but meets them inexpensively. The hardware industry is partly responsible for the I/O bottleneck. By using the processor speed as the primary focus for their sales efforts, the bus speeds have languished. With respect to the new class of processors, current system bus speeds are greatly lagging. This is something like building a mill which can process 1000 pounds of grain a day, and supplying that mill with a single donkey. There is little use for a fast processor that spends most of its time waiting for data to act upon. Whether this data comes from disc drives, peripherals, or even other processors, today's bus speeds would leave most processors idle, and the next generation of processors will be many times faster. Fiber Channel provides the data transfer capability which can keep current and upcoming processors busy. Impact on Mass Storage ---------------------- Today's fastest interfaces are capable of transferring data at around 20 megabytes per second. However, this speed rating is only for transferring data. All protocol intercommunication occurs at much slower speeds, resulting in a lower effective data transfer rates, typically around 11 megabytes per second. This represents about one-tenth of Fibre Channel's current capability. Fibre Channel drives do not suffer from device protocols occurring at slower speeds, since all communication occurs at 100 megabytes per second, including device intercommunication. In addition to this, the drive itself can be placed up to 10 kilometers away from the computer. This would have two effects on the way mass storage is implemented. First, the amount of data a machine could receive would only be limited to the transfer speed of the drive. For high performance disc arrays this could exceed 50 megabytes per second. Machine and disc storage could finally work to provide real-time, full motion video and sound for several machines simultaneously. With Fibre Channel's ability to work across long distances, these machines could conceivably reside many miles apart. For medical applications, computer design centers, and real-time networks such as reservations systems, this capability would be invaluable. Second, such support for transmitting data over large distances would allow disc drives to be placed away from the computer itself. This would allow for centralized data resource areas within a business office, simplifying everything from site planning to maintenance procedures. Indeed a centralized data resource center would be possible for an entire office complex. The development of the Loop will also provide a huge advantage in implementing large capacity disc sub systems. The Fast/Wide SCSI specification has a theoretical upper limit of 16 total devices attached to a single host. The practical maximum is 6 devices. Fibre Channel supports a theoretical limit of 256 devices for a common host, with a practical implementation of 64 devices. This practical limit is a very conservative figure, and implementation with more devices are easily possible. The Loop allows system designers to build high capacity configurations, well into the terabyte range, with much lower overall cost. Finally, Fibre Channel is a serial communications device which has two immediate advantages. First, the cabling necessary to interconnect Fibre Channel devices is very inexpensive when compared to SCSI cabling. Fibre Channel cabling is also much easier to connect, and replace than SCSI cables, which simplifies the entire process of integration and maintenance for a high capacity data storage system. For corporations that are currently grappling with a the complexity of installation, and high-cost of SCSI cables, this feature will prove invaluable for cutting costs and simplifying installation and upkeep. Secondly, implementing Fibre Channel requires less space on the circuit board than SCSI drives. This reduced space requirement would allow the drive designers to include extended features which cannot currently be implemented. For example, a 3.5-inch form-factor drive with Fibre Channel could be designed with dual-port capability, a feature necessary for use with many mainframes and mini-computers. The space saved on the circuit board by using Fibre Channel would allow for the extra connector and additional circuitry needed for dual-port drives. Conclusion ---------- The Fibre Channel will provide the corporations with data in much the same way the freeway system provided motorists mobility. Access to a vast, interconnected information network which is fast, inexpensive, and flexible. With the adoption of Fibre Channel as an open ANSI standard, its effect on the horizon of computing will be nothing short of revolutionary. We have become very good at processing data; Fibre Channel allows us to move it. The ability to share information will provide the impetus for communication, design and development on a scale not previously possible. By facilitating the fabled data-highway, Fibre Channel will accelerate to the Age of Information, as the steam engine moved us into the Age of Industry.