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Message ID: 3845     Entry time: Tue Nov 2 13:51:40 2010
Author: josephb, yuta 
Type: Update 
Category: CDS 
Subject: RFM slowdown problem 

Problem:

Each RFM memory location which needs to be read by a front end model slows the model significantly.

With no RFM memory locations to be read (replaced with grounds), the c1mcs model runs around 25 microseconds per cycle.

With 1 RFM memory location (MC_L), it runs around 29-33 microseconds.

With 3 RFM memory locations (MC_L, MC1_PIT, MC1_YAW), it runs around 45 microseconds.

With 7 RFM memory locations, the code generally doesn't run at all, going past the 62 microsecond maximum required to be able to keep up with the 16 kHz sample rate.

Last night Yuta somehow got it running with 7 RFM memory locations, but in that case, all the odd numbered RFM channels (1,3,5 as counted by the ipc file) did not work.  It was running at around 55 microseconds in that case.

The c1ioo code which is writing the data to the RFM card is experiencing no such slow down.

Current CDS status:

MC damp dataviewer diaggui AWG c1ioo c1sus c1iscex RFM Sim.Plant Frame builder  ...
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