Capturing Digital Waveform Data From The Serial Output - SA Instruments 1030 Operation Manual

Signal Breakout Module
Once activated, you can set the com port, create a name for the text file, select either
the number of samples to collect or run continuous and start or stop the capture
process. Program status is displayed in a message box.
WaveGrab version 2.03 has the important option to include a flag bit in the output. It is
sometimes of benefit to synch data from the MR scanner or another source with the
ECG, respiration and other waveforms. In that case, a bit from the scanner or another
source can be input to the Model 1030 at the AUX BNC connection of the ERT
Control/Gating Module. In this case if you check to output the AUX GATE in the bit
output and the waveform in the serial output or the BREAKOUT window and if the
"include flag bit in the output" box is selected in the WaveGrab window then the flag/bit
will be output with the waveform data (2 columns of data). This feature allows time
stamping 2 or more waveforms so they can be synchronized for analysis.
The flag bit input at the AUX BNC should be a 5 V pulse >1 msec in duration. The bit
can be displayed in PC-sam by selecting AUX Input in the Cardio Sweep display.

Capturing digital waveform data from the serial output

A 2 byte packet is output at 900 packets per second from the serial port. For ECG each
packet is a measured data point. For IBP & plet the sample rate is 450 samples/sec
and 2 packets are output with the same value. For respiration the sample rate is 225
samples/sec and 4 packets are output with the same value.
The first byte output for the packet has bit 7 = 0 and low bits 0-6. The second byte has
bit 7=1, bit 6=1 if data is deemed stale, bit 5 contains the status of the bit out, and high
bits 0-4.
Revision C, August 2013
16-5