Performance

Dante8 free-running mapping mode

The following table shows the maximum number of pixels/s for MCA mapping mode as a function of the number of boards enabled and the number of MCA channels on the Dante8. The tests were done under the following conditions:

  • MappingPoints = 2000

  • PollTime = 0.01

  • ArrayCallbacks = Enable

  • WaitForPlugins = Yes

  • TriggerMode = FreeRunning

The PresetReal time was decreased in 1 ms steps until the mapping mode acquisition no longer collected the requested number of pixels.

The PresetReal time on the Dante is limited to multiples of 1 ms, so the pixel rate in FreeRun mode is limited to 1000, 500, 333, 250, etc.

Maximum pixel rate in Hz (spectra/board/second) for TriggerMode=FreeRunning

MCA Channels

1 board enabled

2 boards enabled

4 boards enabled

8 boards enabled

1024

1000

1000

1000

500

2048

1000

1000

500

333

4096

1000

1000

1000

1000

Dante8 externally triggered mapping mode

The following table shows the maximum number of pixels/s for MCA mapping mode as a function of the number of boards enabled and the number of MCA channels on the Dante8. The tests were done under the following conditions:

  • MappingPoints = 2000

  • PollTime = 0.01

  • ArrayCallbacks = Enable

  • WaitForPlugins = Yes

  • TriggerMode = Trig Rising

  • PresetReal = 0.1 (does not matter)

The Dante8 was triggered by an external programmable pulse generator. The pulse width was 10 microseconds. The pulse generator was programmed to output 2000 pulses.

The pulse frequency was increased until the mapping mode acquisition no longer collected the requested number of pixels.

Maximum pixel rate in Hz (spectra/board/second) for TriggerMode=Trig Rising

MCA Channels

1 board enabled

2 boards enabled

4 boards enabled

8 boards enabled

1024

6200

2300

900

350

2048

1500

750

340

150

4096

8060

8060

8060

8060

The same results as above were obtained for TriggerMode=Gate High.

In 4096 channel mode all spectra are eventually collected for trigger frequencies up to 8000 Hz. However, in 2048 and 1024 channel mode the maximum trigger frequency is much less before spectra are lost, and the EPICS IOC needs to be restarted.