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rete monitoraggio ambientale partecipativo documentation at https://doc.rmap.cc
https://rmap.cc
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firmware: IST sensor declare not compatible min I2C clock frequency #369

Closed pat1 closed 2 years ago

pat1 commented 2 years ago

https://www.ist-ag.com/sites/default/files/ahhytm_e.pdf pg 15 declare:

SCL clock frequencyfSCL MIN 100 MAX 400kHz

and we use 30Khz clock ...

mbaldinetti commented 2 years ago

Those are the standard speeds at which the I2C bus operates. This does not mean that these speeds cannot be different and in particular lower, as reported by https://www.i2c-bus.org/speed

"...The speed grades (standard mode: 100 kbit/s, full speed: 400 kbit/s, fast mode: 1 mbit/s, high speed: 3,2 Mbit/s) are maximum ratings. Compliant hardware guaranties that it can handle transmission speed up to the maximum clock rate specified by the mode.

This does not imply that a transmission may not take place at any lower speed or even at a somewhat variable bit rate..."