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+# smctool
+
+A Linux userspace tool to read Apple SMC keys. Supports various data types and output formats.
+This tool is a part of the coreboot project.
+
+### Usage
+
+##### Main options
+
+```
+-h, --help:         print help
+-k, --key <name>:   key name
+-t, --type <type>:  data type, see below
+```
+
+##### Output format options:
+```
+--output-hex:  print value as a hexadecimal number
+--output-bin:  print binary representation
+```
+
+##### Supported data types
+`ui8`, `ui16`, `ui32`, `si8`, `si16`, `flag`, `fpXY`, `spXY`
+
+**fp** and **sp** are unsigned and signed fixed point data types respectively.
+The `X` in **fp** and **sp** data types is integer bits count and `Y` is fraction bits count.
+
+For example: `fpe2` means 14 integer bits, 2 fraction bits, `sp78` means 7 integer bits, 8 fraction bits (and one sign bit).
+
+### Examples
+
+Reading battery level:
+```
+smctool -k B0FC -t ui16  # returns Full Capacity of Battery 0
+smctool -k B0RM -t ui16  # returns Remaining Capacity of Batery 0
+```
+
+Reading fan speed:
+```
+smctool -k F0Ac -t fpe2
+```
+
+### License
+
+GPLv2