- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
I am helping debug a custom design that has 3 CY7C65642 on it. There is one that is connected to the host, and then the other two are downstream from the top one. This is a self-powered unit with the reset pin being driven off of the USB power.
My problem is that when I turn on the board, I can see the board enumerating properly on my Windows laptop and it reports the proper VID/PID (I am not using any EEPROM). But then nothing happens (and GANG LED goes dark).
While probing the crystal feeding the main hub, I see it come up for about 500ms, and then go to ground. This, along with the above, leads me to believe that the system is going into a suspend mode, but I don't know why. The device continues to be enumerated in windows, so for some reason windows hasn't felt the need to disconnect it.
Any thoughts? I've spent a couple of days on it and am at a loss at this point....
Solved! Go to Solution.
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
Thank you for getting back with me. After talking things over with a Cypress FAE, it appears that we had our CUR# pins pulled low (since the designer wasn't planning on monitoring the current), which apparently caused the lower devices to not enumerate. Once we pulled those high through a pull-up resistor, everything worked fine. Thanks again.
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
Hello.
Can you provide the snapshot of schematic? We can do a quick check and review it. If you think its confidential, you can create a technical support case and Cypress technical support team will evaluate them.
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
Thank you for getting back with me. After talking things over with a Cypress FAE, it appears that we had our CUR# pins pulled low (since the designer wasn't planning on monitoring the current), which apparently caused the lower devices to not enumerate. Once we pulled those high through a pull-up resistor, everything worked fine. Thanks again.