Model 911 Vdt Keyboard Logic - Texas Instruments 990 Manual

......
I
v.
w
FROM CRU
INTERFACE
LOGIC
{
FROM TIME BASE
GENERATOR
FROM CRU
INTERFACE LOGIC
FROM VIDEO
LINE DRIVERS
(B) 136284
KEYBOARD
{
UART
CRA2Q
_,...-1
TRB RR!
FROM CRU
4~ RR2
~
INTERFACE LOGIC
TR7
CRA3Q
TR6
~
RR3
TR5 RR4
_____.......
~
TR4
RR5
_____.......
" - - -
TR3
RR6
_____.......
TR2
RR7
r-
_ /
TRI
RRB
/
o -
SFD
0 ----' ROD
1 - PS
1 - WLSI
o - SBS
KEYBOARD o -
F 1 1
KBPEL
ACKNOWLEDGE
PE
LATCH
FROM TIME BASE
HSQ
GENERATOR
t=
TC
FE
t--
KEYBOARD
i
ACKNOWLEDGE
KEYBOARD
SYNCHRONIZER
INTERRUPT
RC OE
t--
LATCH
RESET LATCH
KBR DYL
L504 1 - CRL
DR
PRE
WORD IQ
J
Q
KBACKQ
D Q
KBASQ
D
Q KEIAK'l. NKBAKQ
KBTL
i5RR
-
TO
LS109 LS273 LS273
NCR13P
-IO
CLK
RI
1 - WLS2
TBRE
KBTBREL
I - -
1 - K
Q t - -
.--
CK
,...--
CK ,...---
i'BRL
MR
TRE
1--
J
CLR CL CL
~
FROM CRU
CRA9Q
INTERFACE
NDOT4
LOGIC
FROM TIME HSQ
NRL BASE
GENERATOR
BKBINL.
FROM CRU
RL
INTERFACE
LOGIC
Figure 1-34. Model 911 VDT Keyboard Logic
KBD, 0-7 ,Q
TO CRU
INTERFACE
LOGIC
1
TO CRU
l
INTERFACE
LOGIC
PRE
1
--1
J
LS109
-C
CLK
TO VIDEO
LINE DRIVERS
1 ---1K
CLR
~
~NKBTBRL
~
,.......-
-
LS02
~
NRKBL
----
Q
KBDRQ
-
Q~
TO CRU
INTERFACE
LOGIC