Allows a limited number of DS18B20 read failures
before stopping the printer. This is designed to
tolerate spurious read errors, while still stopping
for serious issues.
The printer will stop when the sensor
fails to report a value five times in a row.
Implementation works as follows:
The MCU reports any read errors using a new "fault"
parameter in its answers.
The Python code tracks the number of errors
and triggers the shutdown. This paves the way for
more sophisticated error handling in the future,
as well as an example for other sensors to follow.
Signed-off-by: Lorenzo Pfeifer <Lorenzo.Pfeifer+github@googlemail.com>
Initial commit of code to support 1-wire (Dallas) sensors such
as the DS18B20. Requires Linux kernel drivers to create a file
in /sysfs which is read by this module, and temperature
typically returned to a temperature_fan.
Signed-off-by: Alan Lord <alanslists@gmail.com>
Signed-off-by: Josh Headapohl <joshhead@gmail.com>
functionpointer