IBM System/360 Field Engineering Manual

INPUT/OUTPUT OPERATIONS
SI Format
I Opcode flrlT!h7!1J Bi I
0 7 8 15 16 19 20
rz1 ;;z111 ///f!Zl/!71Zl ~~: I
o m 21
Dl(Bl) } HIO SIO TCH TIO
Sl ' ' '
CHANNEL ADDRESS WORD
Device
Address
Key J 0000 J
Command Address
CHANNEL COMMAND WORD
Command
Code
7 8
Data Address
Flags loo o Vll!l/!/ 171/J
Count
31
63
(:ommand Code assignments are listed in the following table. The symbol
X iridicates that the bit position is ignored; M identifies a modifier bit.
CODE
MMMMOlOO
xxx x 1 00 0
MMMMllOO
MMMMMMO 1
MMMMMM! 0
MMMMMM! 1
Bits 0-7 specify the command code.
COMMAND
Sense
Transfer in channel
Read backward
Write
Read
Control
Bits 8-31 specify the location of a byte in main storage.
Bits 32-36 are flag bits; refer to OPERATION CODE tables for flag
bit assignments.
Bit 32 causes the address portion of the next CCW to be used.
Bit 33 causes the command code and data address in the nextCCWtobeuse
Bit 34 causes a possible incorrect length indication to be suppressed.
Bit 35 suppresses the transfer of information to main storage.
Bit 36 causes an interruption as Program Control Interrupt
Bits 37-39 must contain zeros.
Bits 40-47 are ignored.
Bits 48 .. 63 specify the number of bytes in the operation.
36 S/360
IBM CONFIDENTIAL

IBM System/360 Specifications

General

Brand	IBM
Model	System/360
Category	Desktop
Language	English