comedi_arm_channel — arm a subdevice channel
#include <comedilib.h>
| int comedi_arm_channel( | comedi_t * device, | 
| unsigned int subdevice, | |
| unsigned int channel, | |
| unsigned int source ); | 
This function arms a specified channel of a subdevice.  It may, for
example, arm a counter to begin counting.  The source parameter specifies what source
should trigger the subdevice to begin.  The possible sources are
driver-dependant.  This function is only useable on subdevices that
provide support for the INSN_CONFIG_ARM
configuration instruction.  Some subdevices treat this as an
instruction to arm the whole subdevice and ignore the specified
channel.  For such subdevices, comedi_arm is normally
called instead.