IBM 5280 Distributed Data System - Index of

Hex Length inDisplace- Bytes (inment Hex) Description12 Main Microprocessor Flags:Bit(s)13 Data Set Flags:Meaning0 0 There is more than one external status subroutine.They are accessed via a subroutinetable.External status conditions are handled byone subroutine.1 An error occurred when opening a data set.2 SCS conversion data set; logical buffer isempty.3 SCS conversion is in progress fGr this lOB.4 1 SCS last line status flag.5 1 An error detected by the main microprocessoris outstanding.6 CLOZ operation logically complete.7 SCS purge in progress, set during CLOZoperation.Bit Meaning When 114 2 Address of,data set name.16 System use only.0 The lOB is open.Logical buffer is within the physical buffer.2 Diskette is using double physical buffers ..3 Diskette microprocessor is waiting for ashared data set conflict to be resolved. Theshared data set is being used by another lOB.4 On open, the logical record and block sizeare set to equal the sector size.5 I/O MPU requires repeat of last command.The main MPU decrements the externalstatus table return address for repeat whena RETURN instruction is used.6 Not used.7 SCS continuation of transparent data acrossphysical buffers, or data set keys are inascending order.17 Partition address, high-order byte: The value in byte 17is added to each address in the lOB to convert it to anabsolute storage address. This byte also points to thebeginning of the partition lOB and is used to find tableaddresses.Main Storage Data Areas 81