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Tic T500 Python3 homing problem

Hi. I’m trying to run Tic500 in Python 3, on Raspberry PI. All commands seem working, but when I try homing, I have the following error: "Error: Unknown option: ‘–home rev’ "

the code looks like that:
ticcmd(’-d’, tic_serial_number , ‘–home rev’)

What do I do wrong?

Thank you

Hello, vaasG.

I moved your post to its own thread since it seemed different enough to warrant it’s own topic.

Your code is close to being correct, but --home and rev need to be passed in as separate arguments, similarly to how you have -d and tic_serial_number. Like this:

ticcmd('-d', tic_serial_number, '--home', 'rev')

Brandon

Thank you Brandon. Works now:)

1 Like

Hi, I have another related question: when trying to read variable “Misc flags 1”, Python returns error KeyError: ‘Misc flags 1’
the code is just:
status = yaml.load(ticcmd(’-d’, tic_filters , ‘-s’, ‘–full’))
flags = status [‘Misc flags 1’]

What might be the issue?

You are receiving an error because ticcmd -s --full does not output anything that matches “Misc flags 1”. You can run that command in a shell to see what it outputs.

Brandon

Thank you Brandon. I’ll use ‘position uncertain’ output to figure out if my homing procedure was done. After a set of commands:

ticcmd -d  00299119 --energize
ticcmd -d 00299119 --exit-safe-start
ticcmd -d 00299119 --home rev
ticcmd -d 00299119 -s --full

the list shows that the reverse limit is not active, although ‘position uncertain’ is in ‘No’, and I know that the sensor is active.

In ticgui I can see that the reverse homing sensor is active (yellow) when I click ‘home reverse’ in the menu.

If you know why this is the case please let me know, otherwise, as I mentioned, I’ll just use the reading from the ‘position uncertain’

Hi, if I run ticcmd -d 00299119 -s --full, I can see the readings from RC pin:
RC pin:
Digital reading: 0 or 1 (depends if the switch is on/off).

How can I read this value in Python? What command should I use? At the moment I use the following set:

status = yaml.load(ticcmd(’-d’, tic_filters , ‘-s’, ‘–full’))
user = status [‘RC input’]

But I get KeyError: ‘RC input’ error message.

thank you

None of the ticcmd commands are blocking, including --home, so if you are reading the status right after telling it to home, the limit switch probably hasn’t been triggered yet.

I moved your post about reading the RC input back to this thread since it is essentially the same problem that you posted about previously; ticcmd -s --full does not output anything that matches “RC input”. I recommend trying each of these lines of code and looking at the output from each of them so you can understand what is going on:

print(status)
print(status["RC pin"])
print(status["RC pin"]["Digital reading"])

Brandon