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Model T940 User Manual
Publication No. 980938 Rev. K
DR8 Driver/Receiver Board G-4
Astronics Test Systems
in
Chapter 5
.
DR8 Driver & Receiver I/O
Figure G-3 illustrates the configuration and control of the DR8 Driver &
Receiver I/O (TTL).
DATA
EN
RH
AUX 1-4, CH 1-32
VCC
GND
37.4
Ω
I/O CONTROL
510
Ω
510
Ω
RL
74LVC2G125
74LVC2G125
DB
FRONT
PANEL
Figure G-3: DR8 Driver & Receiver I/O Block Diagram
Signal Descriptions
DATA
Channel and auxiliary data output signals from the Data
Sequencer to the TTL output drivers.
EN
Channel and auxiliary enable output signals from the Data
Sequencer to the TTL output drivers.
RH
Response High input signals to the Data Sequencer from
the TTL input receivers. 1 = good 1, 0 = good 0.
RL
Response Low input signals to the Data Sequencer from
the TTL input receivers. 0 = good 0, 1 = good 1.
AUX 1-4
Four TTL signals used to input or output test signals. See
Configuring the AUX Channels
in
Chapter 5
.
CH 1-32
These are UUT Bi-directional TTL I/O channels from the
DR8 Drivers and Receivers.
VCC
TTL Power (~5.0V).
Control Logic
The control logic contains the registers, memory and logic that allow the
digital board to interface and configure the hardware.
Signal Descriptions
I/O CONTROL
Signals used to control isolation, termination, NV data and
load relays