Spectrum Brands MC.31XX - Manual (Page 90)

90 MC.31xx Manual
The different synchronization options Synchronization (Option)
Synchronization (Option)
This option allows the connection of multiple boards to generate a multi-channel system. It is possible to synchronize multiple Spectrum boards
of the same type as well as different board types. Therefore the synchronized boards must be linked concerning the board’s system clock and
the trigger signals.
If no synchronization is desired for a certain board you can exclude it by setting the register shown in the following table. This must be done
seperately for every board that should not work synchronized.
The different synchronization options
Synchronization with option cascading
With the option cascading up to four Spectrum boards can be synchronized. All boards are connected with one synchronization cable on
their sync-connectors (for details please refer to the chapter about installing the hardware).
As the synchronization lines are organized as a bus topology, there is a need for termination at both ends of the
bus. This is done in factory for the both end-boards. The maximum possible two middle-boards have no termination
on board.
When synchronizing multiple boards, one is set to be the clock master for all the connected boards. All the other
boards are working as clock slaves. It’s also possible to temporarily disable boards from the synchronization.
The same board or another one of the connected boards can be defined as a trigger master for all boards. All
trigger modes of the trigger master board can be used. It is also possible to synchronize the connected boards only
for the samplerate and not for trigger. This can be useful if one generator board is continuously generating a test-
pattern, while the connected acquisition board is triggering for test results or error conditions of the device under test.
For the fact that the termination is set in factory the order of the syncronized boards cannot be changed by
the user. Please refer to the boards type plate for details on the board’s termination. End boards are marked
with the option „cs-end“ while middle boards are marked with the option „cs-mid“
When the boards are synchronized by the option cascading
there will be a delay of about 500 ps between two adjacent
boards.
The figure on the right shows the clocks of three cascaded
boards with two channels each, where one end-board is de-
fined as a clock master. Slave 1 is therefore a middle-board
and Slave 2 is the other end-board. The resulting delay be-
tween data of the two end-boards is therefore about 1 ns.
Please keep in mind that the delay between the channels of
two boards is depending on which board is actually set up as
the clock master and what boards are directly adjacent to the
master.
Synchronization with option starhub
With the option starhub up to 16 Spectrum boards can be synchronized. All boards are connected with a seperate synchronization cable
from their sync-connectors to the starhub module, which is a piggy-back module on one Spectrum board (for details please refer to the chapter
about installing the hardware).
When synchronizing multiple boards, one is set to be the clock master for all the connected boards. All the other boards are working as clock
slaves. It’s also possible to temporarily disable the synchronization of one board. This board then runs individually while the other boards
still are synchronized.
The same board or another one of the connected boards can be defined as a trigger master for all boards. All trigger modes of the board
defined as the trigger master can be used. It is also possible to synchronize the connected boards only for the samplerate and not for trigger.
This can be useful, if one generator board is continuously generating a testpattern, while the connected acquisition board is triggering for
test results or error conditions of the device under test.
Additionally you can even define more than one board as a trigger master. The trigger events of all boards are combined by a
logical OR, so that the first board that detects a trigger will start the boards. This OR connection is available starting with starhub
hardware version V4.
Register Value Direction Description
SPC_COMMAND 0 r/w Command register of the board
SPC_NOSYNC 120 Disables the synchronization globally.