9. For output spooling devices, the VDEVEXTN field (displacement X'10') contains the pointer to the virtual spool extension block, VSPXBLOK. 10. The value of the VDEVFLG2 field (displacement X'38') describes the
Reserve/Release flags.Value of X'80' X'40' X'20' X'10' Comments Process-virtual Reserve/Release commands
Minidisk reserved byVDEVUSER VDEVBLOK to get device end when minidisk released Virtual I/O waiting for release on minidisk
11. For Reserve/Release minidisks,VDEVRRB (displacement X'3C') contains
the address of theVRRBLOK. The address of the first RCHBLOK is found in the ARIOCH field
(displacementX'3B4') of the PSA (Prefix Storage Area). General register
6 contains the address of the active RCHBLOK. Examine the following
fields:
1. The real channel address is found in the RCHADD field (displacementX'OO') • 2. The value of the RCHSTAT field (displacement X'04') describes the
status of the real channel.Value of RCHSTAT Comments X'80'--ChanneI-busy X'40' lOB scheduled on channel X'20' Channel disabled X'01' Channel dedicated
3. The value of theRCHTYPE field (displacement X'05') describes the
real channel type:Value of X'80' Selector channel X'40' Block multiplexer channel X'20' Byte multiplexer channel X'01' S/370 type channel (S/370 instruction sUFport) 4. The RCHFIOB field (displacement X'08') is the pointer to the first IOBLOK in the queue and the RCHLIOB field (displacement X'OC') is
the pointer to the lastIOBLOK in the queue.
Reserve/Release flags.
Minidisk reserved by
11. For Reserve/Release minidisks,
the address of the
(displacement
6 contains the address of the active RCHBLOK. Examine the following
fields:
1. The real channel address is found in the RCHADD field (displacement
status of the real channel.
3. The value of the
real channel type:
the pointer to the last