Campbell CR9000, Instruction Manual

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Section 7. Measurement Instructions
7-31
Bursting to CPU and PAM Memory
The maximum continuous throughput rate for measurements made by the
CR9052DC to be processed and stored by the CR9031 CPU is 2500 Hz for 1
to 24 channels. The measurement rate can be increased by bursting data into
CPU memory or PC cards in the CR9080 PAM Module. In this mode, the
CR9031 and CR9052DC support a sustained aggregate sample rate (the sum of
the sample rates on all channels) of 50 ksamples/sec (100 ksamples/sec to
rotating-media PC cards). The burst buffer size is limited by the capacity of the
CPU memory, or by the capacity of the PC card. The triggered burst option
allows experimenters to save only the data of interest before, during, or after, a
trigger event.
The following program bursts CR9052DC measurements onto a PC card.
' CR9052 example program #3
' Measure 5 channels on the CR9050 at 10 kHz on the +/- 5000 mV range with triggered
' burst buffering on a PCMCIA card.
' Burst trigger when channel 1 exceeds 4000 mV, or when flag 1 is on.
' Subsequent recordings are appended to end of preceding recording.
const pam_slot = 4
const cr9052_slot = 8
const sample_len = 1000
' record 1000 samples for each trigger
const scans_past_trig = sample_len-200 ' this makes the trigger the ~200th sample point
Public Flt_in (5)
units Flt_in = mV
Public flag (1)
'------------------- Data Tables -------------
DataTable (FiltData, True, -1)
DataInterval (0, 0, usec, 100) ' do not explicitly save the time stamp with each record,
‘data can still be collected to the pc with time stamps
PamOut(PAM_Slot, CardA, 0, -1) ' data table is ring memory, maximum size
Sample (5, Flt_in(1), ieee4)
EndTable
'------------------- Program--------------------
BeginProg
ResetTable (FiltData) ' start with fresh data table
while (True)
Scan(100, usec, 1, sample_len)
BeginBurstTrigger (1)
' VoltFilt (Dest, Reps, Range, FSlot, Chan, FiltOption, Excit, Mult, Offset)
VoltFilt (Flt_in(1), 5, mV5000, cr9052_slot, 1, 2, 1, 1.0, 0.0)
EndBurstTrigger ((Flt_in(1)>4000) or flag(1), scans_past_trig)
CallTable FiltData
Next Scan
Flag(1) = False ' turn flag 1 off to eliminate multiple triggers
wend
EndProg