Have I bricked my BT Hub?

Installing and Using OpenWrt
1

I have been trying to flash my BT Home Hub 5, following and reading the guides I have done the following (solderless technique):

Using blu-tak to hold the pins in place I connected as follows:

TX -> R78
RX -> R77
Pin 1 -> boot_sel2/R45

I then made a short form the usb to R45.

Is there another ground required in addition or is the above all that is required. I cannot get a clear picture of the connections in any single guide.

When I powered the modem up and then release the short to R45 I was only seeing garbled characters in my putty session. Then with the modem powered up I again made a short to the usb earth and the green led lights flashed, I quickly removed the short but now I don't have any leds at all, even if I power down remove all wires.

Have I bricked / fried my modem? Is there a way back or is it toast?

Thanks in advance,

Alan.

2

Yes, you need a ground connection between the BT Home Hub and the serial adapter for the serial communication to work reliably. Any convenient ground connection point should work, such as the case of the USB socket.

3

garbage in putty's usually due to incorrect speed settings.

4

Thanks for the replies - I also read that the garbled characters could mean the wrong baud rate, I set Putty to use 115200 initially. It was when I changed this to 9600 and tried again that I had the incident meaning the LED's stopped working. In hindsight seems the lack of ground to the serial was the issue.

Any thoughts on why my LED's are dead?

Thanks.

5

Where does the R45 pad need to connect to, on my usb toserial i have pins:

GND
CTS
VCC
TXD
RXD
DTR

6

For a serial connection, you need

  • GND to GND
  • Tx to Rx
  • Rx to Tx

Keep these connected as long as you are working at the HH5 on the bench.

Before powering up, add a temporary connection between R45/boot_sel2 and GND.
This configures the CPU to load u-boot from serial instead of flash.
After power-up, remove this temporary connection, but keep the three wires for the serial connection as mentioned above.

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