SICS counter handling

This section deals with the SICS interface to single counters. Where the SICS counter concept may include several monitors per counter. A counter is, again, a named object which takes commands. A word or two has to be lost about the SICS handling of preset values for counters. Two modes of operation have to be distinguished: counting until a timer has passed, for example: count for 20 seconds. This mode is called timer mode. In the other mode, counting is continued until a control monitor has reached a certain preset value. This mode is called Monitor mode. The preset values in Monitor mode are usually very large. Therefore the counter has an exponent data variable. Values given as preset are effectively 10 to the power of this exponent. For instance if the preset is 25 and the exponent is 6, then counting will be continued until the monitor has reached 25 million. Note, that this scheme with the exponent is only in operation in Monitor mode. The commands understood are:

• countername SetPreset val sets the counting preset to val.
• countername GetPreset prints the current preset value.
• countername preset val With a parameter sets the preset, without inquires the preset value. This is a duplicate of getpreset and setpreset which has been provided for consistency with other commands.
• countername SetExponent val sets the exponent for the counting preset in monitor mode to val.
• countername GetExponent prints the current exponent used in monitor mode.
• countername SetMode val sets the counting mode to val. Possible values are Timer for timer mode operation and Monitor for waiting for a monitor to reach a certain value.
• countername GetMode prints the current mode.
• countername mode val With a parameter sets the mode, without inquires the mode value. This is a duplicate of getmode and setmode which has been provided for consistency with other commands. Possible values for val are either monitor or timer.
• countername SetExponent val sets the exponent for the counting preset in monitor mode to val.
• countername GetCounts prints the counts gathered in the last run.
• countername GetMonitor n prints the counts gathered in the monitor number n in the last run.
• countername Count preset starts counting in the current mode and the the preset preset.
• countername status prints a message containing the preset and the current monitor or time value. Can be used to monitor the progress of the counting operation.
• countername gettime Retrieves the actual time the counter counted for. This excludes time where there was no beam or counting was paused.
• countername getthreshold m retrieves the value of the threshold set for the monitor number m.
• countername setthreshold m val sets the threshold for monitor m to val. WARNING: this also makes monitor m the active monitor for evaluating the threshold. Though the EL7373 counterbox does not allow to select the monitor to use as control monitor in monitor mode, it allows to choose the monitor used for pausing the count when the count rate is below the threshold (Who on earth designed this?)