Euphonix CO-600 Change-Over System For New Core DF66 Redundancy
15
Front Panel Switch
Each Switch Front Card has a 3-position toggle switch, which allows for forcing either
DSP Bank connector to be connected to the I/O connector. It also has a center “Auto”
position which automatically sets the Bank A or Bank B connection based on conditions.
This toggle switch will only function when the “OK” LED is lit and the board is operating
normally. Otherwise, the bypass relay will release and force a connection between the
primary DSP Bank A connector and the I/O connector.
Automatic Operation
When a Switch Card is operational with its “OK” LED lit, and the front panel switch is
in the “Auto” position, the card selects the Bank A connector unless any of three signals
for each Switch Card is asserted. The three signals are:
Individual Back Plane Switch – a separate hardware driven signal for each
1.
individual Switch Card.
Global Back Plane Switch – a single hardware signal effecting all Switch cards
2.
simultaneously.
SPI Test Switch – a separate software driven signal for each individual Switch
3.
Card.
If any of these three signals are asserted, the Switch Card will connect the DSP Bank B
connector to the I/O connector. This condition will continue until the operator clears the
condition or power is removed.
Individual Back Plane Switch
NOTE:
Not used when connected to Emix or MaxAir.
The individual back plane switch is asserted when a predefined GPIO input pin is
grounded. There is one pin for each Switch Card. The condition will cause just the
indicated Switch Card to select Bank B. It will continue to select Bank B until the
condition is cleared via the Ethernet or serial interface, or by front panel control.
The operator can clear the condition by moving the front panel toggle switch for that
card to the “A” position. Setting of the individual back plane switch by GPIO input will
be prevented while the front panel switch is in the “A” position. Returning the switch to
the “Auto” position will allow the individual back plane switch to re trigger if the GPIO
input pin is still grounded.
The individual back plane switch position will be preserved through power cycles.
The individual back plane switch states are not dependent on which Switch Cards are
installed. That is, an individual back plane switch can be asserted even if no card is
installed.
