Texas Instruments 990 Maintenance Manual page 35

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945408-9701
I
,..
TTYHX
-
-
-
TTY HR
CURRENT
CUR-
RENT-
r -
LOOP
LOOP
TTYLX
DEVICE
MODE
-
-
CRUDATAOUT
-
-
TTY LR
-
-
CRU B ! T , 1 2-
t
5
-
I
-
IMODSELA-
-
/
RCTE
-
-
-
STORECLK-
-
DTRE
COMPUTER
TTY/EIA
-
CRU
-
MODULE
-
INTERFACE
TLIORES-
RTSE
-
-
-
-
EIA
+5V,±12V, GND
XMTDE
DEVICE
-
-
- -
--
CRUDATAIN
PCTS
EIA
-
- -
MODE
CRUINT-
PDCD
-
-
-
-
RCVDE
-
-
ff WITH KITS
22651_5.0~QClO 1 l0.QQ2 •
-
DCDE
RCRE BECOMES RiNG iNDiCAfOR (RI)
l
-
~
RCRE*
-
-
DSRE
-
(A)i 33022 A
Figure 4-5. Full Duplex ITY /EIA Module Interface Diagram
Clear Read Request ( CLRRRQ). Logic 0 or 1 resets read request interrupt logic.
Clear New Status Flag (CLRNSF). Logic 0 or 1 resets new status flag.
Enable Interrupts. Logic 1 sets interrupt mask latch.
Diagnostic Mode. Logic I sets diagnostic mode latch.
4.3.1.2 CRUBIT,12-15. CRUBIT,12-15 are the CRU bit select field of the 12-bit address word
from the computer. They are used by the module to activate the latches and logic mentioned in
paragraph 4.3. I. I.
Change 1
28
Digital Systems Division