LIS-SDI Rev.
2
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4.4 Power-up sequence
At power-up, the card performs a self-check, and initiation. The manual mode switch is then
sampled. If manual mode is enabled, the other switch settings are read and the state of the
card set accordingly. If manual mode is disabled, the state the card held the previous time it
was used is read from EEPROM. The interplay between the EEPROM, the switches and the
GYDA (or other) controller adhere to the following simple rules:
•
If a GYDA controller is present in a system, it can always override manual settings.
•
If the manual mode is used together with a GYDA controller, the LIS-SDI will initiate as
determined by the switches, and may then be overridden by the controller.
•
If the manual mode is not used, the LIS-SDI will initiate as determined by the state of the
EEPROM. It is subsequently controlled by the GYDA controller.
•
At any time, when a state change is done, whether it is by switches or GYDA, the state is
stored in the EEPROM as soon as it is detected.
4.5 When an input signal is lost
If SDI input disappears
If the SDI input disappears the output will be blanked SDI video.
If Black&Burst disappears
Given that stable SDI input and Black&Burst exists. If the Black&Burst disappears, the SDI
input will still be output, but there are two important differences:
The internal clock will now be locked to the SDI input clock. The lsync mode (linesync
mode) is now disabled.
If both inputs disappear
The output will be black video locked to the onboard crystal. This is not a reference clock,
and drift out of video specification cannot be precluded.
4.6 Warm up time
The LIS-SDI uses a voltage controlled crystal oscillator (VCXO) to generate a clock that is
locked to Black&Burst or SDI. At power up the LIS-SDI may use as much as 12 seconds to
lock to a Black&Burst or SDI source.
5. Module status
5.1 GPI - General Purpose Interface
The GPI output is an open collector output.
Max current: 100mA
Summary
: The LIS-SDI card remembers the settings it had the last time it held power.
