IOE IOE defines symbolic addresses of elements and other information associated with an I/O operation requested by a task. MPIIOQ and SELIOQ in SVECTORS point to queues of I/C elements for the multiplexer and
selector channels, respectively.
The IOTABLEA field points to the address of an I/O table defined by IeTAELE, which is
described in this secticn.
o 4 8 IOSTAT C lOADDR Hexadecimal Field
Displacement Name ------------ 0 IONEIT DS 1F 4 IOSOBQ DS 1F
8 IOSTIT EQU *
Bits defined in IOSTAT SENSING---EQO-X'80'--- CHANDONE EQU X'40' 8 IOTABLEA DS 1F
C IOADDR DS AL2
E IOSBCHAN DS 1X F IOID DS 1X lONEIT IOSUBQ IOTAELEA IOSECHAN IOID Field Description, Contents, Meaning
Address of next active I/O element
Address of first inactive I/e element for a
given subchannel for current IIC operation
(first tyte of IOTABLEA)
Flag set to 1 while automatic sense is
active
Flag set to 1 when subchannel terminates
Address of I/O request table in task storage
Address (cuu) of the device requesting
current I/O operation
Subchannel address; 1-byte; assigned by MSUP ID of task associated with this I/O cperation
is 1-byte and assigned by MSOP 254 IBM VM/370 Data Areas and Control Block Logic

ICTAELE IOTABLE defines symbolic addresses for items used in processing an I/C interrupt request.
The first five fields are filled in by the task to convey information about the I/O request to the supervisor. The last three fields are filled in ty the supervisor to
convey status infor.ation about the I/O operation to the task.
o
4
8
c 10 14
Hexadecimal
Displacement
------------ 0 4
6
7
8
c
D
14 SIOCODE Field
Name IOSYNCH DS DEVCUU DS SENSREQ DS DEVCODE DS PROGADDR DS SIOCODE ENDCSi DS END SENSE DS DEVCUU 1F
AL2
AL1
AL1
1F
2F
AL1 in ENDSENSE TYPPUN EQU 1'80'------ TYPPRT EQU X'40' IOSYNCH SENSREQ DEVCODE PROGADDR ENDSENSE Field Description, contents, fteaning Synchronization lock for I/O operation
Address (cuu) of device associated
with this I/O operation Numter of sense bytes requested on unit check
1-byte Vft/370 device type code
(not used by I/O manager)
Address of channel program for the
l/C operation
1-byte SIO condition code
return information SIO condition code
Ending CSi with composite status
return information
Requested return sense informaticn
on unit check CSi status type code for the punch V8/370 type code for the printer
Section 3. RSCS Iata Areas and ContrGl Blocks 255