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merging USB receive

Well, I’ve managed to merge the USB receive portion into the main program that reads and processes tracks.  This means I no longer need an external program to receive the data, to write it to a file, to read the file into the main program. Now I just run the main program which reads the SX directly.

I’m sort of unhappy because I can only get a max of 38.4k to work, and I’m not sure if this is a flow-control issue or what.  38.4K isn’t horrible, translates to about 3 seconds for each track.  I really don’t want to do the math, but I know this number isn’t acceptable.  The problem is the PC here and it’s somehow related to buffers, flow-control, etc.

My USB interface supports up to 3mbps, and I’ve tested it at 921600 baud.  I tried 57.6k and looked at the output on the scope, and the output looks perfect.  So it’s the PC giving me a hard time.  I’ve got to read the SDK closer though, and adjust some settings.

I’m going to play with it a little longer, and if I can’t mAake progress on it, I’m going to move onto something else and optimize later.  There are many things to do and I don’t want to waste time on getting one thing perfect before moving on….

 

keith

Amateur Electronics Design Engineer and Hacker

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