Why does my REPL session always have this output

[rhubarbdog]

When a program terminates and I have a serial terminal open why do I always have this output. I have other micropython devices they just print Micropython version details and the >>> prompt.

Code: Select all

Type "help()" for more information.
>>> AT^SQPORT?
Traceback (most recent call last):
  File "<stdin>", line 1
SyntaxError: invalid syntax
>>> AT
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
NameError: name 'AT' isn't defined
>>> AT
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
NameError: name 'AT' isn't defined
>>> AT
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
NameError: name 'AT' isn't defined
>>> ~x~~x~

[ThomasChr]

Does ist also loose characters if you type? Then I also have this problem... resetting and reconneting a few times helps.
As to the cause: I have no idea!

[Roberthh]

That's most likely the modem manager on your PC, which tries to activate what it takes as a modem. Please deactivate or better deinstall the modem manager.

[kapoira]

it happens to my with linux in fedora 30

but i think i have only see it, in micropython 1.10, in micropython 1.8 i don't remember it, (perhaps it's my memory, or that i was using fedora 25/26)

[ThomasChr]

@Roberthh: Thats a great tip. Yes, sounds like something is trying to access the port and modem manager is very plausible. Will check that. Thanks a lot!

[cefn]

See https://github.com/adafruit/circuitpython/issues/611 for a bit more detail and workarounds, at least for Debian-based and Ubuntu-based Linuxes.

[dhylands]

Another source of mysterious AT sequences can happen when you use minicom. Some versions may send out init or reset sequences (minicom thinks its talking with a modem) which will confuse Micropython. It's possible to configure your setup to not send these.

I prefer to use picocom over minicom as I find picocom is much easier to get up and running.

[cefn]

Potentially could use 'vanguard shell' to connect.

It wraps pyserial's miniterm with a micropython-specific terminal configuration and has never spoken to a modem in its life

https://pypi.org/project/vgkits-vanguard/