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11 years, 4 months ago.
Windows program interrupt process.
Now, I am developping communication program between LPC1768 and PC. PC OS is Windows XP. LPC1768 is connected to PC by USB. Communication protocol is virtual serial. Baud rate is 921600. I set PC program to occur serial interrupt when LPC1768 send data to PC. But PC program does not work. The interrupt occr in the beginning, but after a while the interrupt does not occur. Does not Windows OS work for fast rate? But when hyperTerminal running on PC and LPC1768 are communicating on 921600 baud,communicationg data is shown on hyperterminal without stop.
1 Answer
11 years, 4 months ago.
Hi, what kind of data are you transmitting from the MBED that requires this high a bit rate?
To me it sounds like you are missing an interrupt (or not processing an interrupt) and from then on it is downhill. PC hardware can do a lot of things, but they are not very good at interrupt handling. With a bit rate of 921.600 you will get 92.160 interrupts per second, which is one interrupt every 10 microseconds, and if your PC is doing something with interrupts disabled for longer than that, you have the problem.
I would start out with something slower (say 115.200) and then go up or down from there. Maybe do a little processing on the MBED, such as compression (as in packing 2 digits into 1 byte) or similar stuff.
Hope this helps Henrik