Why use driver? How it works? Need to understand more of that.

[Thomas Heyndrickx]

Hello everybody, 

I'am sorry to ask for that but i don't really understand what do the driver ? 

I would like to know what's the différence between a communication with driver and a communication with only GPIO4 on the RPI? 

Is it because the RPI has limitation to generate the sequences ? Or is it for other reason everything i know is that the driver allow to grow the 1-wire bus but not how it works. 

Thankyou for your attention and your answers. Sorry for my English it's not my mother tongue

TH

[Brian C. Lane]

Do you mean what's the difference between using a GPIO pin and a device,
like the DS9097U?

The reason not to use a GPIO pin is that, especially under linux,
consistent realtime is hard to do, and the timing of the waveform used
by the 1-wire bus is critical for it to function. So we use a device
like DS9097U which handles the timing for us.

--
https://www.brianlane.com

[Thomas Heyndrickx]

Yes that's it,

The difference between using a GPIO pin and a device, 
like the DS9097U? 

Is it only to generate good timing ? Why when i use device the length of my bus is large than without devices ?  The devices drives more current or voltage or is it only because of the timing is more accurate ? 

Thank you for your answers.