What is the best way to read high rate serial data?

My goal is to read 14 bytes of binary data from an instrument over RS232 serial (baud 460800) at 2000 Hz. I have not gotten a high speed serial card yet so I am currently using the standard serial port (115200 baud) and reading at 400 Hz. I configure the serial port, flush the buffer then enter a while loop to read the incoming data. I have a visa read 14 bytes per interation every 0.0025 seconds (400 Hz). However it seems the sensor is spitting out data faster than labview can read it because bytes are accumilating at the port. After a while the buffer fills up and the program fails.
Is there a better way to do this?
Would it be better to read larger amounts of data less often, e.g. like 1400 bytes every 0.25 seconds?
Thanks
Solved!
Go to Solution.
Attachments:
serial_read.jpg ‏161 KB
serial_read.vi ‏19 KB
bytes read.png ‏20 KB

Here is a producer consumer approach.... not tested
The unwrapping of the string could be done in a better way (didn't spend much time on it, not tested!! Just a quick mod from another post)
Can't remember what is faster scan from string or match pattern or regular expression .....
Avoid any frontpanel objects in the serial read loop to keep that thread independent from the GUI thread. Blocksize (128) should be optimized...
EDIT: The scan loop will not work
Greetings from Germany
Henrik
LV since v3.1
“ground” is a convenient fantasy
'˙˙˙˙uıɐƃɐ lɐıp puɐ °06 ǝuoɥd ɹnoʎ uɹnʇ ǝsɐǝld 'ʎɹɐuıƃɐɯı sı pǝlɐıp ǝʌɐɥ noʎ ɹǝqɯnu ǝɥʇ'
Attachments:
ProducerConsumerData 2.vi ‏29 KB

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