Operating instructions
M300USERSGUIDE SEA
SETUP
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projects. If some of your acquisition rates are higher, then pick a system frequency that is at least as
high as the maximum acquisition frequency.
Mode
These are the BC635/BC637 modes allowed by the M300. See the BC635/BC637 documentation.
The valid modes are, None, Time Code, Free Running, 1 PPS, RTC and GPS.
The mode must be None, when there is no BC635/BC637 present in the system.
The mode must be None, when the user doesn’t want to sync to BC635/BC637.
DifferenceLimit
When the BC635/BC637 mode is set (not None), this is the number of seconds to set as the
maximum difference allowed between the BC635/BC37 clock and the M300 clock.
This is 0.001 s for normal operation. If the value is too small, this will cause the M300 to make a
large number of unnecessary adjustments. If the number is too large the clocks will not have a good
synchronization.
ClockSource
When the BC635/BC637 mode is set (not None), this should be set to external, and a clock source
must me provided to the board.
If a clock source is not available to the BC635/BC637, this must be set to internal.
IRQSource
The M300 can use the system board as the main source for acquisition. This is the recommend IRQ
source.
If the system doesn’t have a system board, such as a laptop, but still wants to do acquisition, the PC
Clock can be used to drive the acquisition. This mode doesn’t have the accuracy of the M300 system
board. We don’t recommend using it unless there is no other way.
Done
(See “Done” on page 104).
Default
(See “Default” on page 104).
Cancel
(See “Cancel” on page 104).