Plexon Stimulator 2.0, Руководство пользователя

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Neurotechnology Research Systems
Stimulator 2.0 - 40 -
The file can contain up to 1000 amplitude values. The duration parameter can range from 1 µs to
65535 µs. The current amplitudes can range from -1,000,000 nA to +1,000,000 nA in steps of 1 nA.
Note however that the actual resolution of the stimulator output in stimulation mode is ~ 30 nA
and all current amplitudes will be rounded to the nearest possible output value. For example an
amplitude value of 15 nA will be rounded down to 0 nA and an amplitude value of 16 nA will be
rounded up to 30 nA.
6.5.2 Variable Sampling Rate
In the variable sampling rate file format, the first line of the file contains the keyword “variable”.
The second line of the file codes for a current amplitude and the third line of the file codes for the
duration that the amplitude on line two should be played Subsequent lines in the file code for
additional amplitude duration pairs. When the stimulation pattern is played back, each current
amplitude is played for the specific duration associated with that amplitude. The variable sampling
rate format is especially useful for coding complex patterns of rectangular pulses.
The file can contain up to 500 amplitude duration pairs. The duration parameter can range from 1
µs to 65535 µs. The current amplitudes can range from -1,000,000 nA to +1,000, 000 nA in steps of
1 nA. Note however that the actual resolution of the stimulator output in stimulation mode is ~ 30
nA and all current amplitudes will be rounded to the nearest possible output value. For example an
amplitude value of 15 nA will be rounded down to 0 nA and an amplitude value of 16 nA will be
rounded up to 30 nA.
As with rectangular pulses, the arbitrary pattern should be charge balanced, meaning that the same
amount of current is deposited and withdrawn from the electrode. The Stim2 software will
automatically analyze the loaded file and give a warning if the net charge is not zero.