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Altera_Forum
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15 years ago

USB fT245 max II

HI, im working with Max II . it has a CPLD and an device usb the FT245, do anybody have worked with that?, i did an example with labview and VHDL, i can communicate with pc, but the signal TXE doesnt...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
15 years ago

You need to learn how to use oscilloscope probes correctly.

Your oscilloscope traces show huge amounts of ringing. This is typically due to having a large loop of ground wire in your ground clip. Try using a shorter ground lead, or a probe tip that allows you to probe both the signal and ground with a very small amount of space between them.

Cheers,

Dave