Table Of Contents - Xerox 7250 Reference Manual

CONTENTS
1. GENERAL DESCRIPTION
Check-write (X1OSI) 15
Read (X'121)
15
Introduction 1
Test (X'13 1 )
15
Features
2 Test Mode 1 15
System Components 2 Test Mode 2 (Check-write) 15
T est Mode 2 (Read) 16
Key Events 16
Start Input/Output 16
Unusual End Conditions 16
Channel End Conditions 16
2. FUNCTIONAL DESCRIPTION
4
Fau It Conditions 16
Transmission Error Conditions 16
Equipment
4
Incorrect Length Conditions 16
Model 7250 Controller
4
Status Response 17
Status Response 4 Overflow and Carry Indicators 17
Cartridge Initialization 4 Condition Codes 17
Error Checking 4 Devi ce Status Byte 17
Model 7251/7252 Disk Drives 4 Operational Status Byte 17
Operator Control Panel 4 Additional Programming Considerations 20
Spindle Assembly
5 Information Protection
20
Read/Wri te Heads 5
Command Chaining and Data Chaining
20
Start-Up Cycle 5 I/O Interrupt Envi ronment 20
Write Protect Feature 6 IOCD Flag: Xerox 530 and Sigma 3
Model 7254 Disk Cartridge 6 Computers
20
I/O Operational Flow 6 10CD Flags: Xerox Sigma 5/6/7/8
Service Cycles 9 Computers 20
Order Out 9 Sequence of Activity
20
Data Out 9
Data In 9
Order In 9
Terminal Order 9
Disk Organization 9
Tracks
9
4. OPERATIONS 27
Sectors
11
Cylinders 11 Control Panels 27
Data Organization 11
Operator Control Panel 27
Parity
11
LOAD/RUN Switch 27
Cylinder Address 11
LOAD Indicator 27
Data Presentation
11
READY Indicator 27
Data Access
11
CHECK Indicator 27
Track and Sector Incrementing
11
PROTECT Indicator
27
Examples of Automatic Incrementing 12 Controller Maintenance Panel 28
Error Conditions 12 Operating Procedures
29
System States 12 General Operating Practices
29
Operational Devices 12 Disk Drive Interlocks
29
Data Transfers 13 System Power Turn On Procedure
29
Recommendations 13 Disk Drive Start Up Procedure
29
Cartridge Loading and Unloading
Procedures 31
Disk Drive Stopping Procedure
31
System Power Turn Off Procedure 31
Cartridge Procedures 33
3.
PROGRAM INTERFACE 14
General Handling Procedures for
Cartridges
33
Device Orders
14 Label ing Cartridges
33
Write (X 1011)
14 Inspecting Cartridges
33
Read (X 102 I)
14 Cleaning Procedures
34
Seek (X I
03 1 )
14 Storing Cartridges
34
Sense (X'04I)
15
Usage Log 34
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