The usb 2.0 hub design is follow TUSB4041PAPEVM Schematic. And use the external eeprom for PID/VID setting. The eeprom bin file is showed as picture.
In our application, the Host is the Mac mini (mac OS system). The hub is used to communicate with our product, and the product will power cycle which means the device will disappear and reconnect.
There exist a strange phenomenon: if the hub first power on ; or mac mini restart ; the hub will drop (the mac mini can't read hub device) still for about 6s when our product power cycle and reconnect. And It is particularly important to note that this phenomenon only occurs under the conditions mentioned above.
We capture the data of USB, and show error as below photo. Could you please help analyze it and provide some suggestions?
Hi. Thanks for your reply.
The issue is happened in our project. and the schematic and block diagram showed as below:
The mac mini try to install the system into the product through USB2.0.And the restore process have two steps. there exist a reboot between two steps.In the normal case, Mac mini only need to spend 3s to find the device (testing product). But in the abnormal case, Mac mini will spend at least 8s to find the device, and we check the system log of mac miin, find that there exist a reconnection of the hub.But it is strang that this phenomenon only occurs under the conditions (the first test after power on hub board or restart Mac mini). We suspect that there might be some abnormality in the configuration of TUSB4041?Could you help to review the eeprom setting as the last meassage showed?
For below two suggestion,I will upload the result once it done.
Can you remove external EEPROM and test again? hub should work in its default mode.
Can you take waveform for 3.3v/1.1v and GRSTz signal
Can you remove external EEPROM and test again? hub should work in its default mode.
Answer: there is nothing improve to use the default mode.the issue still exist.
Can you take waveform for 3.3v/1.1v and GRSTz signal
Answer:Capture the waveform of 3V3,1V1,GRSTz signal. And there have not voltage drop or shake.we can refer to the screenshot for detail. The GPIO means the time of fail trigger.
