The NI-9237 is an analog acquisition C-series module for strain gages and load cells. I'm using it in a NI-9144 EtherCAT backplane connected to a cRIO-9024 (on a NI-9114 backplane). It's used with four 5000Lb load cells. While the system runs in hybrid mode (there are other module interfaces that only work in FPGA mode), I hope to run the NI-9237 module in scan mode, but there is an "offset calibration" feature/property of the module that I would like to use that is not accessible under scan mode. The Offset Cal property is accessible to FPGA code. My question is the following..
Does the NI-9237 scan mode interface turn on and take advantage of the offset calibration/correction feature within the FPGA portion of the "RIO Scan Interface" code or does it leave it ignored and turned off? I cannot find any document that says that scan mode does use it but I also cannot find any document or person who can say that scan mode does not use it. As it removes instrumentation offsets from the measurement, it seems like something that would be good to have on so it seems reasonable that the scan interface might naturally use it.
Even though the FPGA and input module hardware can in most cases acquire readings considerably faster than the scan interface can accept them, allowing for the possibility of oversampling with averaging or filtering before delivery of a measurement to the scan interface, the "Under the Hood" reference above seems to imply that only individual measurements are made and delivered by the FPGA to the scan engine. Is this implication correct?
“Each module performs as many conversions as possible to provide the most recent I/O values to I/O variables configured for direct I/O access, which bypasses the scan and reads directly from hardware.”
