When I connect both the D+ and D- wires to the board, the connection between the testing Cool Disk with the computer is lost!

[Pe3a-XaH]

When I connect both the D+ and D- wires to the board, the connection between the testing Cool Disk with the computer is lost!

[ataradov]

What is Cool Disk?

[Pe3a-XaH]

Hi,

I meant USB Flash Drives Storage.

In my country it is more famous as Cool Disk.

[ataradov]

This sniffer will not be useful with flash drives. They still should function, but that depends on the quality of the connections. But sniffing will not work, since USB drives enumerate as High-Speed devices and this sniffer can only work with Full-Speed devices.

Try with something simpler, like a keyboard or a mouse.

[Pe3a-XaH]

I tested with a non-smartphone and it seems to work.

I am using putty terminal with speed 576000 to communicate with pico.

But my question is how to save buffer data inside a file?
Because it is not completely possible using copy and paste from Putty terminal.

I also get the following error at first, but after pressing the S key a couple of times to capture, it seems to get only small parts of the exchanged data correctly.

Capture started
Capture stopped
Synchronization error. Check your speed setting.

Capture buffer is empty

[When press (s) key many times ...]

1583027 : NAK
1583033 : IN: 0x02/2
1583036 : NAK
:
:
1583116 : NAK
1583122 : IN: 0x02/2
1583125 : NAK
1583133 : IN: 0x02/2
1583135 : DATA0 (7): 43 4d 47 52 3d 33 0d
1583143 : ACK
1583400 : IN: 0x02/2
1583403 : NAK
1583410 : IN: 0x02/2
1583413 : NAK
1583420 : IN: 0x02/2
:
:
1583946 : IN: 0x02/2
1583948 : NAK
... : Folded 1 frame

Capture buffer:
0 : RESERVED
1869129088 : RESERVED
4154500480 : RESERVED
0 : SPLIT: HubAddr=0x77, SC=1, Port=05, S=0, E=0, ET=2
... : Folded 1 frame
103123066 : SOF #551
103123078 : IN: 0x00/0
103123088 : IN: 0x00/0
103123098 : IN: 0x00/0
:
:
103123714 : IN: 0x00/0
103123724 : IN: 0x00/0
103123733 : IN: 0x00/0
103123829 : MDATA (280): 41 2a f8 07 f8 07 00 00 fc 03 01 00 fe 01 00 ff ...
17 : DATA1 (4294967294):
33 : DATA1 (43400): 25 06 20 15 27 2a 02 00 00 00 11 00 00 00 e9 8b ...
103141441 : IN: 0x00/0
103141450 : IN: 0x00/0
103141461 : IN: 0x00/0
:
:
103141568 : IN: 0x00/0
103141578 : IN: 0x00/0
0 : RESERVED

[ataradov]

Get a better terminal that lets you save things into a file. The baudrate setting does not matter, since it is a purely virtual port.

The synchronization errors are common if device is already working and you start the capture. This sniffer assumes that the line is idle and if you start the capture in the middle of the packet, then it will not be able to synchronize properly. There may be a way to improve it, but I don't have time at the moment and in the end there is only so much PIO can do.

The optimal use for this is to start the capture, then plug in the device. This way you are guaranteed to start in the idle bus state.

[Pe3a-XaH]

Thanks a lot

[ataradov]

I've just pushed an update that should address a lot of synchronization issues. I expect it to be much more robust now.

[Pe3a-XaH]

Hi,
Thank you for your update.

I used the sniffer by Tana (https://github.com/tana/pico_usb_sniffer) for my job, because it makes Wireshark (.pcap) output.

Both of sniffers can not sniff full speed devices.

I used it series with a USB Isolator to reduce high speed devices to full speed mode, but this trick did not work for me and both of sniffers ( Tana and yours) makes many error packets.

[ataradov]

What isolator did you use? They generally don't do anything active to reduce the speed. They often just make HS devices not work at all.

Does the device itself work as expected? Does OS show that it has enumerated as an FS device?

Also, not all HS devices can fully function at an FS speed. But they still should not generate errors.