Difference: AMC13UserManual (37 vs. 38)

Notes on generating high L1A rates (above 100kHz)

For LHC Phase 2 upgrade prototyping it is desirable to generate triggers up to around 750kHz. The AMC13 can do this but two settings must be changed from the defaults.

First, the fake data generator event size must be reduced. This can be accomplished with the following (setting the size to 0x10 allows triggers well above 750kHz if only one fake AMC is enabled).

> wv CONF.AMC.FAKE_DATA_SIZE 0x10

Second, to get above about 670kHz the CMS trigger rules must be disabled:

> wv CONF.LOCAL_TRIG.RULES 3

(see section above for detailed documentation).

To get 800kHz fixed rate one can use:

> localL1A b 50

Or 800kHz random:

> localL1A r 800000

Finally, note that various commands in the AMC13Tool2 reset the CONF.LOCAL_TRIG.RULES to the default 0 so one must include the command to reset this in any script or software.