PESA Cheetah 1024x256, Manual

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C
HEETAH
S
ERIES
S
WITCHERS
– C
HAPTER
11
81-9059-0570-0 Rev. C
Proprietary Information of PESA S
WITCHING
S
YSTEMS
, I
NC
. 152
11.6 3500 S
ERIES
S
YSTEM
C
ONTROLLER
C
ARDS
The Cheetah may contain up to two redundant 3500 Series System Controllers (see Figure 67). If the
primary controller fails, the secondary controller automatically resumes all of the primary controller
functions. The System Controller, working in conjunction with 3500 Series Control System software,
enables users to configure and operate a switcher system from a standard IBM compatible PC. The
System Controller interfaces between the routing switcher and all user-controlled elements, including
RCPs, PCs, etc. Based upon configuration data input during setup and installation, the System
Controller sends appropriate I/O control signals to the Cheetah 64x64 Video Matrix Card.
FIGURE 67: 3500 Series System Controller Board Assembly Front View
11.6.1 GND
This test point provides a convenient ground connection when measuring voltages at the other test
points on the 3500ProSystem Controller Card.
11.6.2 +5V
The voltage measured between this test point and GND is the output of the voltage regulation circuit
and should be 5.0VDC (±0.1VDC).
11.6.3 +BATTERY
The voltage measured between this test point and GND is the output voltage of the backup memory
power source and should be greater than 2.0VDC when power has been removed from the board.
11.6.4 Battery ON/OFF Select Switch
This SPDT toggle switch is used to enable and disable the backup memory power source. Early
designs of PESA system controllers used a battery for backup power. This switch was used to prevent
the battery from discharging during prolonged storage.
The 3500 Series System Controller uses a capacitor as a backup power source, which does not need to
be isolated during storage. This switch should be in the ON position at all times.
11.6.5 Reset
This SPDT momentary pushbutton switch is used to manually reset the 3500 Series System Controller
in the event of system failure or lockup (similar to a warm boot on a PC). To reset the controller,
press and hold this switch for about three seconds.
11.6.6 Mode
This SPDT toggle switch is used in a dual-controller system to designate the primary controller and
the backup controller. Set the Mode switch to ACTIVE on the primary controller, and to STANDBY
on the backup controller. In a single controller system, this switch has no effect.