Real-Time Project PWM

[embedded1988]

Hello Everybody!

I need some help regarding my real-time project, here i am attaching the FPGA VI which shows 8 channel PWM signal generation, and five cuurent sensors using NI9201 AI module and 3 voltage senses. I need guidance whether i should do my calculations in FPGA and then log current values in RT VI or fist transfer to RT VI and then do calculations there, current sensors are bi-directional upto 200Amps.Following is the calculation:

I = (Current Sensor Vout-Offset)*100)          ;Sensor is 10mV/A

Please suggest me a structure of the program how should i proceed. How and where to do calculations, send controls to FPGA(frequency,Blanking time,%Duty) and where to save data.

I need to save a complete parameter list with time stamp for ex. every 100ms.(Freq,%duty,blanking time,currents,voltages and powers so on...)

Thanx in advance!

Best regards,

azy

[reschri]

Hi,

that depends on the performance you need.

quote:

whether i should do my calculations in FPGA and then log current values in RT VI or fist transfer to RT VI and then do calculations there

When all your doing is saving your date and do a multiplication than it you should be fine yousing your RT-System. You aquire data and save your Signals every 100 ms. The Signals need to be scaled first and get a timestamp. That shoul be no problem for the RT-CPU.

When do you need to process data on the FPGA?

When the calculation need to be done faster then the CPU of the RIO-System cannot provide (digital filtering i.e). Or, when you want to aquire data, process it and putting it out as fast as possible.

The advantage of programming on the RT side: you do not need to compile after every change.

Regards

René