[Tutor] truncated dictionary return

[richard kappler]

I have a script that reads sensor values gathered by an Arduino board from
serial as a dictionary, said values to later be used in the AI for Nav &
Control. Here's the script:

#!/usr/bin/python

def sensorRead():
    import serial
    from time import sleep

    sensors = {}
    sensors = dict.fromkeys('Sonar1 Sonar2 Sonar3 Sonar4 Dewpoint
Temperature Humidity Light'.split())

    arduino = serial.Serial('/dev/ttyACM0', 9600)
    sleep(1)
    line = arduino.readline().strip()
    line = line.lstrip('{').rstrip('}').strip()

    d = {}
    for item in line.split(','):
        item = item.strip()
        key, value = item.split(':')
        key = key.strip()
        value = value.strip()
        d[key]=int(value)
    return d

I hope that comes through okay, I copied it from the text file so
indentation and such should be fine, if not let me know.

The script works great with one exception. I understand the problem, I'm
just not sure how to address it. The problem is:

The Arduino runs on a constant loop, it reads each sensor, sends the key
and the value to the serial bus in format for python to read it as a
dictionary, lather, rinse, repeat.

Python querries the bus when told. Usually the python script gets the full
dictionary (all 8 values with keys, brackets etc) but sometimes it doesn't.
Sometimes it only gets the last few values, sometimes it gets nothing or
misses a bracket and throws an error. This makes sense. They are not in
sync.

What I need to figure out how to do is have the python script wait until
the next round of values as signified by the opening bracket "{" or check
that it has all 8 values and if not retry or.... something.

Would this be an if/else? try? exception?

I've not yet delved into any of these in my quest to learn python except
if/else and that doesn't feel right for this, so I'm at a loss as to how to
proceed.

regards, Richard

-- 

*Mater tua criceta fuit, et pater tuo redoluit bacarum sambucus*
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