CHAPTER 6: SCSI Description
6.4
Parity
Parity is a method of generating redundant information that can be used to detect
errors in stored or transmitted data.
Data transmitted across the SCSI interface is protected by redundant parity bits:
•
One bit for the 8-bit narrow SCSI implementation
•
Two bits for the 16-bit wide SCSI implementation.
These parity bits detect errors in transmission across SCSI and trigger a resend of
the bad data.
6.5
Signal States
The following paragraphs describe signal values and SCSI IDs.
6.5.1 Signal Values
All signal values are actively driven true (low voltage). Because the signal drivers
are OR-tied, the bus terminator’s bias circuitry pulls false when it is released by
the drivers at every SCSI device. If any device asserts a signal, (for example,
OR-tied signals), the signal is true.
Table 6-3
lists the ANSI-specified and defined
signal sources. Any device can assert RST at any time.
Summary of Contents for SDLT220
Page 1: ...TANDBERG Super DLTTM Product manual Revision 2 June 2002 432589 01 ...
Page 20: ...CHAPTER 1 Introduction ...
Page 34: ...CHAPTER 2 SDLT 220 320 Product Information ...
Page 52: ...CHAPTER 3 Drive Specifications ...
Page 76: ...CHAPTER 4 Installing Your Tape Drive ...
Page 92: ...CHAPTER 5 Using Your Tape Drive ...
Page 104: ...CHAPTER 6 SCSI Description ...
Page 120: ...APPENDIX A SDLT I Tape Cartridge ...
Page 130: ...APPENDIX B DLT IV Tape Cartridge ...