Specifications

7700/7800 MultiFrame Manual
7700ACO2-HD Dual HD/SD-SDI Smart Automatic Changeover
Revision 1.0 Page - 5
2.1. VIDEO CONNECTIONS
HD/SDI INPUT 1A/2A and 1B/2B: The input BNC connector for 10-bit serial digital video signals
compatible with the SMPTE 292M, SMPTE 259M, or SMTPE 310M standard.
HD/SDI INPUT 1A/2A and 1B/2B LOOP OUT: BNC connector for passive looped output of the input
signals.
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LOOP OUT connectors MUST BE terminated with 75 ohms for proper operation.
HD/SDI OUT ACO1 & ACO2: This BNC connector is used to output the video as serial component
video, compatible with the SMPTE 292M or SMPTE 259M standard (same as input) with embedded
audio. One output BNC (labeled) is bypass protected with the A input in the event of a power failure.
GLCK: This BNC connector is used to input a NTSC black burst or tri-level reference signal.
2.2. GENERAL PURPOSE INPUTS AND OUTPUTS
The 7700ACO2-HD has two GPI’s and two GPO’s available via terminal block. The terminal block pin out
is shown in Figure 2-2. Connections are made by putting a force on the inner square (a push-pin or small
flat screwdriver work well), inserting the wire in the adjacent circular opening, and then releasing the force
on the inner square.
GPO 1
GPI 1 GPI 2
GPO 2
GND GND
Figure 2-2: GPIO Pin Out
GPI 1 controls the ACO1 and GPI 2 controls the ACO2. If the GPI is closed to ground, Input A will be the
active output. If the GPI is set to high impedance, Input B will be the active output. The GPI’s are active
low with internal pull up resistors (2k Ohms) to +5V. To make an input active, lower the signal to near
ground potential (i.e. connect to shell or chassis ground). This can be done with a switch, relay, TTL drive,
GPO output or other similar method. Figure 2-3 shows the input circuit for the general purpose inputs.