MtRREC MDRREC retains information for the VM/370 error recording cylinders. I o MDRKEYB I M*1 I/M*2//I/B*3/1 M*4 I////ftDRSPE1////1 8 MDRDTEN 6tR'I'MEN 10 MDRCPID
18 MDRCUA1 MDRVOL 20 MDRSENS Hexadecimal Field
o
2
3 4 5
6
8
C 10 18
1A 20 18
1A
1B
1C
1E 20 18
1A
22 MDRKEYN DS MDRSllS1 DS MDRSllS2 DS MDRSWS3 DS MDRRECNT DS
MDRSPE1 DS
MDRDTEB DS MDRTMEB DS MDRCPID DS 1B
1C
1C
1C
1C
1B
1F
1F
2F Q2ta MDRCUA1 DS 21 MDRVOL DS 61 MDRSENS DS 241 MDRSIZE EQU (*-MDRREC) I.Qf JlIQ §,YEEQrt ORG MDRCUA1 DS 21 DS 11 DS 11 DS 21 DS 21 DS 21 I.Qf JIQ.2 §,YE.EQrt ORG MDRCUA1 DS 21 DS 81 DS 21 Type and operating system M*1 Switch byte 0 M*2 Reserved for IBM use M*3 Reserved for IBM use 6*4 Sequence (4 bits) and record (4 bits) Used for sequence number Indicates the record total
Reserved for IBM use
Date
Time
Processor identification and model number primary CUA of device Volume serial number of device
Sense byte data MDR record size
Line address
Control unit address
Device address
Sense and status informaticn
Resource identification
Reserved for IBM use
Device address Userid Resource identification
38 IBM VM/370 Data Areas and Control Block Logic

IHCBLCK MICBLOK contains pointers to control registers, the segment table, and other values
required by the virtual machine assist feature and the VM/370 Extended Control-Program Support (ECPS). This information is needed for the handling of certain instructions and privileged operations requested by the virtual machine. The VMMICRO field of the VMBLCK points to MICBLOK. o MICRSEG 8 MICVPSW 10 MICVTMR Hexadecimal Field
Displacement Name
o
4
8
8
9
C 10 14
14 MICRSEG DS MICCREG DS MICVPSW DS ORG l'IICVIP DS MICWORK MICVTMR MICACF DS DS DS DS ORG MICEVl'IA DS !!i!§ MICLPSW EQU MICPTLB EQU MICSCSP EQU l'IICSIO EQU l'IICSTSM EQU IHCSTPT EQU l'IICTCH EQU 1F
1F
1F MICVPSW 1X 3X 1F
1F
1F MICACF 1X in MICEVl'IA --X'80'-- X'40' X'20' X'10' X'08' X'04' X'02' IHCCREG MICWORK MICACF Field Description, Contents, Meaning Real segment table pointer Virtual control register pointer Virtual PSW pointer Virtual interrupt pending bit Virtual interrupt
virtual machine
handle change
external mask
All other bits
is pending; therefore, the
assist feature is net to
of PSW channel masks or
from disabled to enabled.
in this byte must be O. Address of virtual PSW Workspace pointer
Location to be decremented when
interval timer assist feature ECPS is being used
Assist controls
the virtual
of VM/370 Expanded virtual machine assist control bits LPSW simulation PTLE simulation SCKC, SPT simulation SIO simulation STNSM, STOSM. and SSM simulation STPT simulation TCH simulation
15 DS 3X Reserved for IBM Use l'IICSIZE EQU (*-MICBLOK)/8 Size of tSECT in doutlewords (X'03') Section 1. CP Data Areas and Control Blocks 39