SEAGATE TECHNOLOGY, INC. Customer Technical Support FAX Network +1 408 438-8137 Customer Technical Support Bulletin Boards (300-9600, 8-N-1) 旼컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컫컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴커 � United States +1 408 438-8771 � United Kingdom +44 628 478011 � 쳐컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컵컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴캑 � Germany +49 89 140-9331 � Singapore +65 227-2217 � 읕컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컨컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴켸 (C)opyright 1993 ST-12550W SCSI-2 Fast Wide (Barracuda 2) (aka ST-12551N) J01컴컴커 �袴袴袴袴袴敲 (see 1냄 � REAR VIEW � below) 읕� 훤袴袴袴袴袴� 1커 컴컴컴횶4-1컴컴� �"� | �"쿕4 1-6 � �"�(see below) | (TOP) J5 �"耗J4-6커 � 34________________1 旼� �1�/袴袴袴袴�\ | | �( 利利利利利利利利� )固::::::납 0 0 0 0 팠 � � \컴컴컴컴컴컴냐컴�/ � 컴 牡�5횳횳�12� � 1 68 pin I/O Cable� 납납납 : : : : : : Connection 납납납 � � � � � 2 납납납 � � � � � � Spindle Synch Cable Connector 컴冒납납 Enable Drive 컴컴� � � � � � (pin-11 SSREF, pin-12 ground) 납납� Terminators * � � � � � Remote LED Connector 컴컴컴컴컴컴冒납� Reserved 컴컴컴컴컴� � � � � [pin-9 cathode (neg), 납납 (default OFF) � � � � pin-10 anode (pos)] 납납 Parity Disable 컴컴컴� � � � 납납 Enable Motor Start 컴컴� � � SCSI ID = 8 컴컴컴컴컴컴컴컴컴컴컴冒납 Delay Motor Start 컴컴컴켸 � SCSI ID = 4 컴컴컴컴컴컴컴컴컴컴컴켸납 (10 sec * ID) � SCSI ID = 2 컴컴컴컴컴컴컴컴컴컴컴컴冒 Write Protect Enable 컴컴컴� SCSI ID = 1 컴컴컴컴컴컴컴컴컴컴컴컴켸 SCSI ID = 0 (none) Mating cable connector: AMP 786090-7, Male 68-pin Drive connector: AMP 749721-7, Female 68-pin 旼컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴커 � J01 - Terminator Power Jumpers 쳐컴컴컴컴컴컴컴컴커 읕컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴켸 � Terminator power from the drive. �1컴� * (default) 度퀑� � � Terminator power from pin 26 on the 靈� SCSI bus. 編編 咆鞭 Terminator to the SCSI bus on pin 26. 靈� * 빗빗 度쏵 Terminator power to the SCSI bus and 靈爐�* drive. 빗빗� 度쏵� * Valid for single ended drives only. Note: ST-12550WD (differential model) does not come with any provision to use Termination resistors. Therefore, SCSI bus needs to be externally terminated. ST-12550W UNFORMATTED CAPACITY (MB) ________________2572 FORMATTED CAPACITY (xx SECTORS) (MB) _____2139 AVERAGE SECTORS PER TRACK ________________81 rounded down ACTUATOR TYPE ____________________________STRAIGHT ARM TRACKS ___________________________________51,433 CYLINDERS ________________________________2,707 user HEADS ______PHYSICAL______________________19 DISCS (3.5 in) ___________________________10 MEDIA TYPE _______________________________THIN FILM RECORDING METHOD _________________________ZBR RLL (1,7) TRANSFER RATE INTERNAL (mbits/sec)________34.3 to 56.5 SPINDLE SPEED (RPM) ______________________7,200 AVERAGE LATENCY (mSEC) ___________________4.17 BUFFER __W/WD_____________________________1024/512 KByte Read Look-Ahead, Adaptive, Multi-Segmented Cache INTERFACE ________________________________SCSI-2 FAST WIDE BYTES PER TRACK __________________________50,888 average SECTORS PER DRIVE ________________________4,177,781 TPI (TRACKS PER INCH) ____________________3,047 BPI (BITS PER INCH) ______________________52,187 AVERAGE ACCESS (ms) (read/write)__________8.0/9.0 Drive level without controller overhead SINGLE TRACK SEEK (ms) ___________________0.6/0.9 MAX FULL SEEK (ms) _______________________17/19 MTBF (power-on hours) ____________________500,000 POWER REQUIREMENTS: +12V START-UP (amps) _2.18 +12V TYPICAL (amps) __0.83 idle +5V START-UP (amps) __1.0 +5V TYPICAL (amps) ___0.76 idle IDLE (watts) _________13 LANDING ZONE (cyl) _______________________AUTO PARK IBM AT DRIVE TYPE ________________________0 or NONE Physical: Height (inches/mm): 1.63/41.4 Width (inches/mm): 4.00/101.6 Depth (inches/mm): 5.97/146.1 Weight (lbs/kg): 1.8/0.80 Already low-level formatted at the factory with 9 spare sectors per cylinder and 1 spare cylinder per unit. ZBR = Zone Bit Recording = Variable sectors per track Seagate reserves the right to change, without notice, product offerings or specifications. (11/09/93)