One of the major improvements in 2018 was the upgrade of the PixelFEC firmware which is responsible for programming the modules. The new firmware utilizes a local memory on the back-end DAQ card, which has a segmented structure. It allows to pre-store the configuration data and to program the modules in a more parallelized manner. This upgrade reduced the total configuration time of the detector from ∼30 s to ∼3 s. The pixel detector, being situated very close to the interaction point, suffers from a significant rate of SEUs on front-end electronics and optical components. The general strategy to recover from the SEUs has been to reprogram the detector in regular intervals with a fast configuration scheme. The online software has a functionality which constantly looks for SEU-induced errors and activates a recovery procedure whenever required. A full pixel-level programming during this recovery was not possible with the old firmware as it would have taken too much time, and would have resulted in data loss. Therefore only a partial, readout chip level reprogramming was being performed. However, the new firmware, with local pre-stored data, reprograms the detector with the full pixel-level configuration in less time than needed for the partial configuration using the old firmware. This in turn leads to a quicker and more complete recovery of the detector from SEU-induced errors. More info: CMS CR-2019/081
Figure in png format other formats Description
Pixel_Total.png Pixel_Total.pdf

This plot shows the total configuration time of the Phase-1 Pixel detector. Pixel Front-End Controller (PixelFEC) firmware change drastically reduced the total configuration time.

Pixel_FEC.png Pixel_FEC.pdf

Module configuration time comparing the old and new firmware, including loading of data into the local memory.

Pixel_FSM.png Pixel_FSM.pdf

We reprogram Pixel detector during every state transitions (Pause/ Resume, Stop/Start, Halt/Configure) This plot shows configuration time during state transitions.

Fast configuration time of the pixel detector before and after the firmware update. With the old firmware only a partial configuration was possible, while the new firmware can per- form a full pixel-level programming much faster with pre-loaded configuration data on the local segmented memory.

Topic attachments
I Attachment History Action Size Date Who Comment
PDFpdf Pixel_FEC.pdf r1 manage 13.8 K 2019-12-11 - 15:01 AtanuModak  
PNGpng Pixel_FEC.png r1 manage 76.9 K 2019-12-11 - 15:00 AtanuModak  
PDFpdf Pixel_FSM.pdf r1 manage 13.7 K 2019-12-11 - 15:01 AtanuModak  
PNGpng Pixel_FSM.png r1 manage 72.9 K 2019-12-11 - 15:01 AtanuModak  
PDFpdf Pixel_Total.pdf r1 manage 14.1 K 2019-12-11 - 15:00 AtanuModak  
PNGpng Pixel_Total.png r1 manage 73.6 K 2019-12-11 - 14:57 AtanuModak  
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Topic revision: r5 - 2020-02-11 - KlaasPadeken
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