IBM System/360

Operation Mnemonic Op Code Format
Operands Description
Interruptions Cond code
Start 1/0
SIO 9C SI Dl(Bl) Opr 1 (21-31) identifies the selected chan,
Privileged
O=I/0 oper
ctl unit and I/O device to perform write, op er
initiated
read, read bkwd, control or sense oper.
l=CSW store~
The CAW at loo 48 is fetched, which
2=Chan or ctl
locates the first CCW.
unit busy
The SIO is initiated providing the addressed 3=Not
chan, ctl unit and 1/0 device are available
operational
without pending interrupt errors,
exceptional conditions pending.
Store
ST 50
RX Rl, D2(X2, B2) Opr 1 is stored into opr 2 Prot Unchanged
Adr
Spec
Store Character STC 42
RX
Rl, D2(X2, B2)
Opr 1 (24-31) replaces the character at Prot Unchanged
opr 2's address. Adr
Store Halfword STH
40 RX
Rl, D2(X2, B2)
Opr 1 (16 low-order bits) is stored at
Adr
Unchanged
opr 2's location.
Prot
(Hi-order bits ignored and unchanged)
Spec
Store (Long)
STD 60 RX Rl, D2(X2, B2) FP. opr 1 to opr 2's location
Adr Unchanged
Prot
Spec
Store Multiple
STM
90 RS Rl,R3,D2(B2) Opr 1 thru opr 3 are stored at opr 2's
Adr
Unchanged
location in ascending order. Starting reg Prot
specified by opr 1, ending reg specified
Spec
by opr 3.
(Reg wrap-around possible)
Store (Short)
STE
70 RX
Rl, D2(X2, B2)
FP. opr 1 is stored at opr 2's location. Adr Unchanged
(Low-order FPR ignored and w10hanged) Prot
Spec