Why do I always get an exception raised in this __init__()?

[Alan Gauld]

On 31/08/2023 22:15, Chris Green via Python-list wrote:

>     class Gpiopin:
> 
>         def __init__(self, pin):
>             # 
>             #  
>             # scan through the GPIO chips to find the line/pin we want 
>             # 
>             for c in ['gpiochip0', 'gpiochip1', 'gpiochip2', 'gpiochip3']:
>      
>                 chip = gpiod.Chip(c)                
>                 for l in range(32):
>                     line = chip.get_line(l)                
>                     if pin in line.name():
>                         print("Found: ", line.name())
>                         return
>             else:
>                 raise ValueError("Can't find pin '" + pin + "'")

You don't store the line anywhere.
You need to use self.line
    self.line = chip.get_line(l)
    if pin...

>         def print_name(self): 
>             print (self.line.name()) 
>      
>         def set(self): 
>             self.line.set_value(1) 
>
>         def clear(self): 
>             self.line.set_value(0) 

As you do here.

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Alan G
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