Other Parts Discussed in Thread: USB-PD-CHG-EVM-01,
Hello,
I have a host tablet (type C port) connected to a 6-port USB Hub. The USB hub has 2 USB-C ports and 4 usb2 ports. The host (tablet) can see all the usb2 ports connected to the hub. I am using the TPS25750D version of this chip for host side of the hub (for tablet) and one of the type C downstream ports. I have the TPS chip connected to an EEPROM which I load the configurations from the GUI tool. The Gui version is 7.04.
My configurations for the downstream type C port in the GUI are:
15W, 15W, Power Role: Power Source, Speed: USB2, Data Role: Device or Host (I tried both data roles separately)
With these configurations loaded into the EEPROM, I see that the TPS boots up correctly and is in APP mode when I do a register read.
I also see that once I connect to a storage device, I read registers that state the power role is a source, and data role is downstream.
I can see the device being powered. But my tablet cannot see it. The storage device works when I connect directly to tablet, but not through my PCB which holds the 6-port hub and TPS chip.
I have the hardware configured like the USB-PD-CHG-EVM-01 except its ADCINx pins are strapped to AlwaysEnableSink, the USB2 data pair goes into the USB hub, and the PP5V is coming from tablet VBUS instead of a regulator.
I have verified my hardware worked before with GUI 7.03 and was able to read storage device. But sadly, I no longer have the binary file that made it work in older version.
I had the same configurations as listed above with either a device or host data role. I don't recall which data role I had working but it seems like I can't get neither to work anymore. I have been testing with the same hardware.
There seems to be some sort of negotiation happening when I probe the right CC line the storage device is attached to. But it looks like a repeat of the same signal that lasts ~15 seconds before it gives up and remains pulled up to about ~1.7V.
Each burst of data happens every ~170ms for ~15 seconds until it gives up.
This doesn't appear to happen on the TPS chip connected to the Tablet. Complete negotiation seems to happen in less than a second and starts to see all the downstream ports instantly (besides the type c downstream port of course)
Please advise.
Thanks,
Victor
