IBM SY31-0458-3 Section 07 62EH Disk free download

File name SY31-0458-3_Section_07_62EH_Disk.pdf

Contents 62EH DISK DRIVE AND ATTACHMENT 7-1 Track Follow Principles . 7-30 INTRODUCTION 7-1 Track Follow 7-30 62EH Disk Drive . 7-:1 Track Follow Waveshapes 7-31 Subframe 7-2 Servo Clock 7-32 Grounding . . 7-2 Servo Clock Waveshapes 7-33 Disk Enclosure 7-2 Phase Lock Oscillator 7-34 Disk Spindle . 7-3 Phase Lock Oscillator Synchronization 7-34 Transducer . . 7-3 Recalibrate Operation 7-35 Actuator Lock 7-3 Disk Ready 7-37 Actuator . . . 7-4 Seek Operation 7-38 Actuator Position Indicator 7-4 Seek 7-38 Circuit Locations 7-4 Actuator Feedback During Seek. 7-39 Motor and Brake . . . 7-4 Seek Waveshapes 7-41 Write Safety . . . . . . 7-5 Power On and Off. 7-42 Data Unsafe Conditions 7-5 Power On and Seek Home 7-43 File Ready . 7-5 Cycle Steal 7-44 Disk Speed. 7-5 Cycle Steal from the Control Processor 7-44 Power On . 7-5 Cycle Steal to the Control Processor 7-45 Disk Format. . 7-5 Control Storage Initial Program Load 7-46 Data Tracks 7-5 Command Bus In 7-47 Sector Format 7-6 COMMANDS 7-48 Disk Addressing .. 7-7 I/O Load Command-I/O Control Load Servo Tracks . 7-8 Command 7-48 Landing Zone . 7-8 I/O Sense Command-I/O Control Sense Guard Band 7-8 Command 7-50 Data Recording 7-8 Sense Interrupt Level Status Byte Command 7-52 Actuator Movement 7-9 Jump on I/O Command 7-54 Seek . . . . . 7-9 ERROR CONDITIONS 7-56 Recalibrate . . . 7-9 Write Data Echo Check