Garbled serial line

Andy Green andy at
Sun Oct 26 02:36:50 CEST 2008

Hash: SHA1

Somebody in the thread at some point said:

| I'm hoping someone can help me out here. I have a GTA01, version B4,
| with debug board version 3. I'm using the latest nightly version of
| uboot. I'm having real trouble getting a console, u-boot or kernel, on
| the serial console. I'm successfully using the JTAG, but the serial
| justs echo '?' when I try to type.
| The strange thing is it is almost working, for example, if I hold down
| a key mostly it echos '?' but sometimes I get the actual character. On
| occasion I've even seen the full uboot prompt.

It's the kind of thing you'd see if the UART clock was slightly off on
one end or the other, and your terminal software was replacing 0x80+
with '?'.  In that case the funny characters would strictly follow the
real traffic and never spew on their own or be totally missing.

If you get unreal spews of rx characters, I would suspect the flat cable
no longer making proper contact and floating the pins, mine lasted a few
months before I had to pinch it by hand in the SMT connector at the
phone and finally it died altogether.

- -Andy
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