Page History

...

• prescaling data by x amount over register
• simulation of modules inside TimeToolCore.vhd
• peak-finding (final parameters)
• programming weights by axi-stream
• emulate LCLS2 timing system in firmware
• divide by the goosedelayed-minus-pedestal (use LUT?)
• virtual evg. (should only require gui tweaks. check with ILA)
• how to handle the git large files
• get rid of gui
  • gui fully removed,
  • still need to make smart and stream line
• programmable event-code & trigger delay (axi bus)
• emulate epix model (send timestamp to front-end board. time stamp should be at the beginning of image packet.).  later:  maybe this isn't necessary because in future we would support camlink-over-fiber cameras with no front-end board?
• save hdf5
• full/deca mode (only 8 bit for deca or full)
• get test stand in 901 working
• start with Matt matched filter algorithm or Abdullah algorithm
• feedback results to Joe Frisch as udp packets or accelerator-style-pgp
• is 8-bits OK for deca? (answer: yes, for interferometry mode)
• understand how system behaves at high rates (do we drop frames? timestamps correct?)
  • reuse matt's firmware for timestamping
  • add in LCLS2 timing (triggering)
  • send full signal to Matt
  • switch from python to C
  • think about running the camera all the time (to send feedback data continuously)
• difference kc705  revisions 1.1 vs 1.2.:  no significant difference according to https://www.xilinx.com/support/answers/59751.html.  Either an FMC problem, or subtle timing issue, or need to specify board rev somehow when synthesizing?
• interface to DRP?
• new front-end boards
  
• touch base with Ryan on code structure issues
• prepare for running in LCLS-I?  If yes:
  • spy on the timestamp multicasts in software (maybe not necessary)
  • take real pictures with lens from Ryan
  • trigger delay and event-code programmable via AXI
  • eliminate gui and save hdf5
  • put all setup commands in python script
  • do we need feedback for laser? (no)
  • run at 120Hz  overnight and validate
• resolve vhdl axi-lite offset constants
  • why doesn't offset 0x400000 (which turns into 0xc00000) work?
  • https://forums.xilinx.com/t5/Synthesis/How-to-display-post-synthesis-integer-constant-values/td-p/692285

...

• Giacomo is doing spatial, Ryan is spectral (roughly speaking)
  • both are interferometric, so the background we had in LCLS1 is mostly gone, but still have some background from stray light, for example
• Formula that should work for both:  (S-B)/(S(goosedelayed)-B(delayed)). (note: division is similar to normalized subtraction:  (S-GB)/G B = (S/GB)-1
• B is different for S and S(goosedelayed) (background at time goose "delayed" is taken)
• Giacomo thinks we won't need the Goose "delayed" subtraction/division for 80% of the experiments
• Giacomo will ensure that we run in a regime where (S(goosedelayed)-B(delayed)) is not close to zero
• sxrx34917 (being analyzed by Giacomo and Stefan Droste).  this data is "zoomed out" in the time dimension, but will be more zoomed-in for LCLS-II.
• S(goosedelayed) comes from moving the laser out of the time window, and is done "offline" according to Giacomo every few hours
• Giacomo wants a fit to the minimum of dI/dt (derivative of I-B) to a parabola
• Giacomo thinks that the feedback will be slower (millisecond level).  Contradicts what we learned before where Joe Frisch was going to do fpga stuff with the laser-locking system
• algorithm should be same for spatial/spectral
• Giacomo wants a way to look at S-Goose when Delay when the timing edge is out of the window.  Tells them if it's on the "right" or the "left".
• Questions for Giacomo:
  • the edge looks big in sxrx34917, do we definitely need to divide? Answer: no, as long as we can set an ROI.  i.e. don't need
  • does the goose contain "delayed" contain background from stray light, for example?  Answer:  goose is "delayed" is the pump laser delayed off the end of the camera image
  • is B just pedestal, or does B include laser-pump?  If it's laser-pump, do we need to use IIR to compute B?  Answer:  B is remaining background (same as LCLS-I) not eliminated by interferometric approach.
  • do we use the same B in the numerator/denominator?  Answer: no

Conversation with Ben Reese (2/13/20)

feb fpga version on feb. 13 2020:
ClinkFebPgp2b_1ch built Tue 16 Jul 2019 10:39:15 AM PDT by ruckman on rdsrv222

_TimeToolKcu1500Root.py has register settings
https://github.com/slaclab/lcls2-timetool/blob/master/software/config/config_20200207_152212.yml

ConfigureXpmMiniSim
TimingRx->TimingPhyMonitor->UseMiniTpg (selects minitpg)
(check clock freq's under TimingPhyMonitor)
switching to real timing need an xpm txreset: see this as RxClkFreq not being the same at TxClkFreq
pipelinedepthfids=90
config_l0_select_ratesel=0x7
7 = 1Hz
5 or 4 is 100Hz
confg_l0_select_enabled=1 starts triggers
TriggerEventManager->TriggerEventBuffer[0]
- has l0 counts
- has xpmpause/xpmoverflow (too much data). xpmoverflow is a sign backpressure not working well enough: reduce pausethreshold. xpmoverflow is latched version of fifooverflow. permanently latch deadtime. needs a clearreadout to reset.
- missing clearreadout going to front end board
- pausethreshold sets when to send deadtime to XPM
XpmMessageCount increments @1MHz
clinkfeb[0]->->clinktop->trigcontrol[0] has a trigger rate
TriggerEventManager->TriggerEventBuffer[0]->masterenable enables triggers going to frontend
TriggerEventManager->TriggerEventBuffer[0]->eventbufferenable enables the fifo that receives the timing frames (and sends the\
m to the batcher eb)
mostly masterenable/eventbufferenable should go together?
eventbufferenable first, masterenable second

xpmmini is only partition(rog) 0.

to switch to realxpm:
- Kcu1500Hsio->TimingRx->ConfigLclsTimingV2
- toggle UseMiniTpg to false

watch kcu1500hsio->timingrx->timingframerx->RxDown (resets to 0 on ConfigLclsTimingV2, latches when link drops)

todo:
- clear readout (workaround TimeToolKcu1500->Application->AppLane[0]->EventBuilder->Blowoff)
- trigger 10us feedback
- edge calculation