IBM 2025 Maintenance Manual page 49

N
0
N
U1
......
I
w
\.0
0
0
WORD
TYPE
1
1
FUNCTION
DECODE
2 3
0 0
0 0
0 0
0 0
0 0
0 0
0 0
0 0
..
_
.............................................
0 1
0 1
0 1
0 1
0 1
0 1
0 1
0 1
--------------------·--
1 0
1 0
1 0
1 0
1 0
1 0
1 0
1
0
-----------------------
1
1
1 1
1 1
1
1
1 1
1 1
1 1
1 1
A SOURCE FIELD B SOURCE FIELD
4
5 6 7 8 9
10 11
0000
=
uo
0000
=
uo
0001
=
U1 0001
=
U1
0010
=
VO 0010
= VO
0011 =
V1
0011 = V1
0100 = GO 0100 = GO
0101
=
G1 0101
=
G1
0110
=
DO 0110
=
DO
0111 =
D1
0111 = D1
1000 = 10 1000 = 10
1001
=
11 1001
= 11
1010 =
TO
1010 = TO
1011 = T1 1011 = T1
1100
=
PO 1100 = PO
1101
=
P1 1101
=
P1
1110 = HO 1110 = HO
1111 = H1 1111 = H1
THE FUNCTION DECODE IS A COMBINATION OF
CONTROL WORD BITS 2, 3, 12, 13, AND 14-
IF THE FUNCTION DECODE IS EQUAL TO 00111,
THE A-SOURCE FIELD ADDRESSES AN EXTERNAL
FACILITY.
IF THE FUNCTION
DECO~E
IS EQUAL TO 01111, THE
B-SOURCE FIELD ADDRESSES AN EXTERNAL FACILITY.
THE SYMBOL -A- USED IN THE FUNCTION DECODE
FORMULAS, REFERS TO ANY OF THE LOCAL STORAGE
SYMBOLS UNDER THE A-SOURCE FIELD.
THE SYMBOL -B- USED IN THE FUNCTION DECODE
FORMULAS, REFERS TO ANY OF THE LOCAL STORAGE
SYMBOLS UNDER THE B-SOURCE FIELD.
THE SYMBOL -C- REFERS TO THE ADDER CARRY
(S3) LATCH
THE SYMBOL)::{ INDICATES AN EXCLUSIVE-OR
FUNCTION.
THE SYMBOL-$- INDICATES AN OR FUNCTION.
THE SYMBOL-*- INDICATES AN AND FUNCTION.
THE SYMBOL-@- INDICATES AN ADD/SUBTRACT
DECIMAL FUNCTION .
FUNCTION WORD
DECODE
TYPE
12 13 14 15
000
B=AX
t1
B 1
001
B = AXH +BL
010 B=AXL$BH
011
100 B=A+B
101 B=AH+BL
110 B =AL+ BH
111 EXT= B
---··--------------------------------------------------
000
B=AX
001 B =AXH
010 B =AXL
011
B = 0 (STOP)
100
B=A
101 B =AH
110 B =AL
111 B =EXT
-------------------------------------------------------
000 A=A
t1
B
001 A=A+B
010 A=A$B
011 A=A*B
100 AC= A+ B + 1
101 AC=A + B
110 AC=A+B +C
111
AC=AL+B+C
______________________________
,..
________________________
000 A=A-B+1
001 A=A-B
010
011
100 AC=A-B +C
101 AC= 0- B + C
110 AC= A± B + C
111 AC= A@B
+
C