Drivers interpreted the uint64 values to the SR_CONF_TRIGGER_SLOPE
configuration setting in different ways. In order to orthogonalize
the API, change the type of the setting to a string with the same
format as uses for logic probes.
The sample rate on the Hameg scopes changes depending on the number of channels
turned on and on the current timebase.
Update the sample rate if any of the above change.
The current vertical division setting (per channel) and the timebase are stored
as a floating point number. This is suboptimal since clients expect us to send
this information to them in form of a rational number.
Store only the index of the current setting since all the supported settings are
already stored inside of an array.
The DF_END packet was send out after all configured frames were fetched, but
devices may stop the acquisition at any point in time and an DF_END will not be
send out in this case.
Send the DF_END packet inside of acquisition_stop() so this can't happen.
The device is after a scan left open and clients that don't call unconditionally
dev_open() will never fetch the initial device state.
Close the device after the scan so clients know they need to open it.