Specify the printf(3) format to be used for displaying input data. This option is ignored in messages that do not read any input from the SMBus device. The format defaults to ‘0x%02x’ for byte input operations, and to ‘0x%04x’ for word input operations. For multi-byte input (block read), the same format is used for each individual byte read from the SMBus.
-c cmd
This is the value of the command byte to be issued as part of the SMBus message.
-f dev
This specifies that dev should be used as the connection to the SMBus, rather than the default of /dev/smb0.
-i incnt
An SMBus message should be generated to read incnt bytes from the device.
-o outcnt
An SMBus message should be generated to write outcnt bytes to the device. The data values to write are expected to follow all of the options (and their arguments) on the command-line, where the number of data bytes must match the outcnt value.
-p
This selects the probe bus modus of operation.
-s slave
The slave parameter specifies which SMBus device to connect to. This option also selects the transfer messages from/to device modus of operation, where a slave address is mandatory.
-w
This option specifies that IO operations are word operations, rather than byte operations. Either incnt, or outcnt (or both) must be equal 2 in this case. Note that the SMBus byte order is defined to be little-endian (low byte first, high byte follows).
Not all argument combinations make sense in order to form valid SMBus messages. If no -c cmd option has been provided, the following messages can be issued:
message
incnt
outcnt
quick read
0
-
quick write
-
0
receive byte
1
-
send byte
-
1
Note in particular that specifying 0 as a count value has a different meaning than omitting the respective option entirely.
If a command value has been given using the -c cmd option, the following messages can be generated:
