Data Flow - IBM 5251 Series Maintenance Information Manual

Data Flow
The next figure shows the data flow of the display
station. The following pages of this section describe
functions performed in each of the major sections of the
display station. Gating and parity checking are not
shown in the data flow; nor are counters and parity
generation shown.
Status Switch
01--------,
r o ; - - - - - - -
I
Planar
-------,
I
Keylock
Magnetic
Magnetic
Stripe
Stripe
Reader
Reader
Adapter
Light
Light
Pen
Pen
Adapter
To
Controller ----""-"
G
I
L_
I/O
Adapter
Cable
Adapter
Read-Only
Storage
I
I
I
I
I
'--0 ___
-4
Microprocessing
I
Unit
I
Read/Write
Storage
Display
Adapter
I
I
I
I
I
I
I
I
_ __________ J
G-
0 Line Check
G~
Line Sync
e
0
Internal Check
e-
0
Storage Check
. A
0
Ready
Brightness
W
Control
Contrast Control
To Next
Terminal
_~(7-
Horizontal, Vertical,
Cable Thru
Feature
4
2
Address
Switches
[ill
T
and Video Signals
,...-------,
Power
Supply
Power
Switch
Theory 5251 M I M 4-3