USB Hubs with FDTI is not working

Dear all,

I have solved lots of my problems here and I am stuck again in one situation.

I have a terminal pc with 2 usb port and I need to expand usb and need to convert rs232. One hub has 4 usb connector and other one has 5 ftdi232rl to convert usb to rs232.

Terminal uses GL850G to expand usb on terminal.

I designed to board because of limited area. and connected one above the other. and made the 8 pin connection between them for data lines and 2pin power supply. My problem is they are not working correctly.

I assemblied 3 board and I have 3 different situatin on them. Fisrtly I connected the board and pc saw the USB hubs but did not see the ftdi converters. Second board saw the 1 hub with ftdi converters. and last one saw the only one hub with usb connectors. I also tested the first board which saw the 2 hub something like this, I removed one ftdi chip because I read something enumeration of the FTDI chips and but it did not see the other ftdi chip. only one chip was connected to boards.
I supplied them from therminal and external supply but nothing changed.

Could you please help me about this situation.

Thanks
Best Regards

Here are the schematics
View attachment Board 1.pdf

View attachment Board 2.pdf

Sure the connection of pin 17/19/26 is correct? Which schematic are you referring to?

Hi,

VCCIO is not connected
RESET is not connected


Klaus

Dear FvM, I found a schematic on web and I made whole thing according to it.

KlausST, what should I connect them, 5V or any other voltage?

Thanks for your replies.
Best Regards.

Hikmet

Hi,

KlausST, what should I connect them, 5V or any other voltage?

Click to expand...

If I had to decide this, i'd look into the datasheet.

Klaus

- - - Updated - - -

Added:

Generally: Don't leave any signal input floating.

FT232R RESET can be unconnected in bus-powered application, VCCIO must be connected either to 5 or 3.3V, in your design obviously 5V.

I don't know if missing VCCIO blocks device enumeration. I also don't know if the shown FE1.1s schematic is correct. Having it picked up somewhere from the internet doesn't actually answer the question.

Dear FvM FE1.1s circuit is correct I have corrected it with the manufacturer. I did not connected the VCCIO.
KlausST told me to look datasheet for the VCCIO and Reset connection and there is a voltage divider with 4.7K and 10K resistors. So it gives 3.3v to Reset pin.Also VCCIO is connected to 5V supply and I made a test like that, I mean I connected 4.7k and 10k to reset and Connected a wire between VCCIO and VCC, it worked.

Thanks for your help KlausST and FVM. :-D :clap: