HP 13255 Technical Information page 18

13255
General Purpose Asynchronous Data Comm Mndule
13255·Ql089/16
Rev AlJG-Ol-76
3.2.2
The 3-to-R decoder provides control siqnals to the other
functlon~l
------
---
----
_
...
_-
--
blocks. Address lines ADORO, AODR2, ADDR3, AOOR5, ADDR6, and WRITE and
I/O are dpcoded and strobed bY REO to realize
lowinq control
~lqnals
are activated as shown
module address Is
---
-
......
-
I/O
WRTTr;:
AODRO
0
0
X
0
0
X
0
,.
X
0 1 1
0
,.
0
0 1
X
0 X
0
X
0
t
X
0
X
selected.
--- ---
AOOP2 ADDP3
X
X
X X
X X
X X
X X
X
X
0
X
t
X
X 0
X 1
X
=
Don't Care
+
=
Rising Edqe
_
...
-
....
---
ADOR5
AOOR6
1
0
0
0
1
0
0 1
1
1 1
0 0
0 0
0
0
0 0
control
pUlse~.
The fo1-
whenever the proper
REO
t
T,oad control regis-
ter from data hus.
t
Load character into
transmit half of
HART.
0
Gate firmware
control word onto
data bus.
0
Gate status word
onto data
hU5.
0
C:ate JTlodlfied status
word onto data bus.
0
Gate received data
from UAFT to data
bus. 'Reset UART's
Data Ready flip-flop
+
Set XECL hiqh
+
Set.
XECIJ
low
+
Turn CD off
+
Turn CD on