Operating instructions
SEA M300USERSGUIDE
SETUP
160
SYSTEMBOARD
Address
(See “Address” on page 103).
State
(See “State” on page 103).
PB/UDP
(See “PB/UDP” on page 104).
IRQ
Controls the Interrupt Request Line used by the System board. Note that some IRQ channels are
reserved and should not be used. By default, the System board uses IRQ 3. Change this value only if
you are sure it will not conflict with another device. SEA recommends that you do not change this
value.
Frequency
The frequency at which the M300 will run the acquisition manager, IRQ. This is also known as
system frequency or maximum system frequency.
The system frequency must be at least as high as the highest desired acquisition event frequency.
The M300 uses the System board to generate the frequency for acquisition. The crystal oscillator
used is a 4.0 MHz clock. This limits the possible system frequencies to some multiples of this crystal
frequency.
When the user changes the system frequency for a project, this might require modifications to other
parts of the system. Acquisition events need to be checked to make sure their frequencies are possible.
If the changes are being made manually, the buf.300 must change sync buffer 0 frequencies.
Some formula and window triggers might be affected.
Typically when you setup a project, find out what the maximum acquisition frequency is, this will
give you a value for system frequency. Normally a system frequency of 100 hz works for most