I would like to write a real time application in Windows CE and NetDCU8.
for testing real time in Windows CE, I wrote two program and load them in two NetDCU8 board. One of them sends a text file(8192 bytes) and another and get file and save it via Serial port. sender sends a block of data and wait for receiver Acknowledgement. I test program in different size of blocks to send (for example 2048, 1024, 512, ...) In receiver I can get file correctly.
But my problem is:
I expected the all receiving process takes T msec but when I measure time, receiveing process takes (T + X) msec and X is different when I change size of block to send and receive. for example I got this:
I calculated T and that must be about 630 msec (in 115200 bps).
Block Size X(msec)
I know X may be included some background process time but I cannot underestand why X is very huge and how can I calculate time and how can I insure about time in real time application.