IBM 7090 User Manual

+PADI5 - XR15
TAO
TAO
+N Set XRA
-R
-A
+N Hold XRA
XRA
Out ut
-R
-P
TAO
TAO
+N S t XRB
-R
-A
+N
-R
-0
-A
-P
D
Output
To Adder
TAO
TAO
+N Set XRC
+N Hold XRC
-A
-R
-P Gate XRC - AD
XRC Output
+P Gate XR - AD
F I GU RE 7. 1-6. INDEX REGISTER
r----
-Gate SR - SR
-
-0
-A
Ace -
SR
r--
+TAO
j~-
MQ - SR
AS - SR
-
MF SB - SR
+TAO
-SR -SI
Adder to SR
-
SI to SR
-=L
..----
Comp SI to SR
~
-A
-
--=R-
-
SR to MQ
'---
Gate OPK
r--
-
-A
-
-A
OPK
SR to ADD
-
-
-
+ Set SR
-Hold SR
-
Gate SR to Adder
-
-A
Gate SR to Adder
Gate
SR to SB
MFSB Out
-
FIGURE 7.1-7. STORAGE REGISTER
171

IBM 7090 Specifications

General

Category	Mainframe Computer
Introduced	1959
Transistor-based	Yes
Word Length	36 bits
Add Time	4.8 microseconds
Memory	Core memory
Memory (words)	32, 768 words