User manual

Section 13: Instrument Control Library (ICL) Series 3700 System Switch/Multimeter Reference Manual
13-84 3700S-901-01 Rev. C / July 2008
channel.write()
Function
Writes a value to a channel.
Usage
channel.write(<ch_list>, <value>, [<width>])
ch_list: String specifying channels to write, using normal channel list syntax.
value: The value to be written to the channel.
width: Optional value that specifies the channel width of the write.
Remarks
For widths greater than 1, the specified channel occupies the least significant byte. For
example, writing the value of 0xff00ff00 to Channel 1 with a width of 4 sets Channel 1
to 0x00, Channel 2 to 0xff, Channel 3 to 0x00, and Channel 4 to 0xff. Writing the value
of 0xff00ff00 to Channel 1 with a width of 1 sets Channel 1 to 0x00 and leaves other
channels untouched.
For digital I/O channels, only a width of 1, 2, 3, or 4 is supported. Any other widths are
ignored. Values written to inputs are ignored. If no specified channel is set for output,
then an error is generated. If a width crosses channels, then only the channels set to
output are affected.
Totalizers, DACs, and switch channels do not support a width other than 1. Specifying
a width greater than 1 results in an error.
For a channel with a power state of OFF, an error is generated. No action is taken on
any channel in the specified channel list.
For DAC channels, the value is expected to be the desired floating point voltage or
current. Also, an error is generated if the value is out of range. No action is taken on
any channel in the specified channel list.
For digital I/O channels, the value becomes the settings of the digital output.
For totalizer channels, the value becomes the new current totalizer count.
The time it takes to execute the write command is affected by the channel delay
setting.
Example
To output a value of 33 to digital I/O Channel 1:
channel.write("1001", 33)