BT HH5a minicom garbled output

hi all

im prolly being a complete retard.. i have followed the how tos but im stuck at the serial connection....

my serial connection works however it does not matter what i do i get garbled output like the speed is wrong.

i have minicom setup as 115200 but all i get is

忿ess CTRL-A Z for help on special keys -彪��� 5忿�y����Su[��������������ysq�忟���c}cw���嬍��[5=7ݿ���彪!#-#1�[5����7��ww[�- ww

someone show the numpty what hes doing wrong please


That you get something suggests that the speed is correct. Check that the voltage level on your serial adapter is correct (3.3 V or 5 V, depending on your router's requirement), that the connections are solid (including any you may have soldered). If that is not the issue, then it may be that there is insufficient pull down/up on either or both of the serial lines.

im using a pl2303 - usb ... direct into the db9 pins 2/3/ /5

pin 2 to R78
pin 3 to R77
pin 5 to GND

db9 sounds a lot like rs232c with was too high voltage levels, your bt hh5a can't cope with mire than 3.3V!

ahh crap... pin 2 is 3.2v but pin 3 is 5v

anyway to pulldown the volage or am i just going to have to buy an rs232 converter

You pull down voltage with a RS232 TTL Pull-Down converter.

Yes, you will have to buy one.

These days it makes more sense to just buy the correct 3.3V/ TTL level usb2serial adaptor.


yer i suppose, i have 2 of these usb to serial pl2303 things in my lappy bag ,, just ordered FTDIusb to ttl 3.3 / 5 V. basically has both vcc 3.3 and 5v pins

should be here tomorrow ... good old amazon


I know you've got a router in your hands right now that you'd like to get going, but for the future I got some decent USB-serial "FTDI" boards off eBay for well under US$5 each delivered. They can be changed from 5 V to 3.3 V with a solder bridge/cut on the board. I haven't tried them under Windows, but they work well enough for me under macOS and Debian/Ubuntu.

The ones without the pins sticking up may be easier to install "permanently" into a router case than the ones with the jumper pins (something like 15 mm high, as I recall). The one with jumper pins don't need handiwork to change from 5 V to 3.3 V, just a shift of the jumper.

i actually made a max 232 years ago (back in the cable modding days) i have just ransacked the place looking for it, but i was unable to find it. thats why i ended up just buying one that would get here tomorrow.

im good with debian,, dont do that winblows nonsense :wink:

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Yesterday's trunk snapshot disabled the network connection. Will have to open the case and install serial connection for the BT HH5a. The 18.06 snapshot couldn't connect to the DSL output to the WAN.

Ahhh so how do you re-enable the wan? Do an earlier snapshot?

Also i have a few rpis hanging around here i could have used one of those as a console box dohh