Ok, I have been trying for a few days now to capture usb signals (from D+/D-) using the Digital Discovery and the HS adapter. Now I have tried very combination of sample rates / hz that I can find and no matter what I do the logic analyzer only captures the first falling edge of the D+ line and nothing more.
For my POC I have connected a USB thumb drive to a USB expansion board and then connected the expansion board GND and D+ (and tried the D-) pins to DIO0. When I plug the USB Thumb drive in my rising edge trigger will take place but the waveforms software (which is the latest from the website) only captures the initial trigger point and no other data
Now if I remove the Digital Discovery and replace its connections with my oscilloscope I see the USB signal transactions taking place between my Windows computer and the usb thumb drive (plugged into the expansion board) and Windows recognizes the drive so I know its the setup that I am using.
As a sanity check, I have disconnected the DIO/GND pins and plugged them into pins 24/GND and then using the pattern generator created a clock signal, with the logical analyzer successfully capturing this data.
Finally, i have taken a similar USB 2.0 thumb drive and wired my probes directory to the USB connectors D+/D-/GND connections (removing the need for an expansion board) and I still get the same results
So a this point I have no clue as to what I am doing wrong and would like to reach out for some guidance if anyone can provide some.
Question
mmessuri
Ok, I have been trying for a few days now to capture usb signals (from D+/D-) using the Digital Discovery and the HS adapter. Now I have tried very combination of sample rates / hz that I can find and no matter what I do the logic analyzer only captures the first falling edge of the D+ line and nothing more.
For my POC I have connected a USB thumb drive to a USB expansion board and then connected the expansion board GND and D+ (and tried the D-) pins to DIO0. When I plug the USB Thumb drive in my rising edge trigger will take place but the waveforms software (which is the latest from the website) only captures the initial trigger point and no other data
Now if I remove the Digital Discovery and replace its connections with my oscilloscope I see the USB signal transactions taking place between my Windows computer and the usb thumb drive (plugged into the expansion board) and Windows recognizes the drive so I know its the setup that I am using.
As a sanity check, I have disconnected the DIO/GND pins and plugged them into pins 24/GND and then using the pattern generator created a clock signal, with the logical analyzer successfully capturing this data.
Finally, i have taken a similar USB 2.0 thumb drive and wired my probes directory to the USB connectors D+/D-/GND connections (removing the need for an expansion board) and I still get the same results
So a this point I have no clue as to what I am doing wrong and would like to reach out for some guidance if anyone can provide some.
thanks.
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