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Task #9610

Milestone #9608: Down Converter Test

Test command list for reading out down converter

Added by John Diamond almost 5 years ago. Updated almost 5 years ago.

Status:
New
Priority:
Normal
Assignee:
John Diamond
Category:
bpmd
Start date:
07/13/2015
Due date:
% Done:

30%

Estimated time:
8.00 h
Spent time:
10.75 h
Duration:

Description

Verify that we can execute a command list that arms the DDC and reads it out and the end of a 0x20 cycle.

rawplot.gif (15.9 KB) rawplot.gif raw mode capture John Diamond, 07/23/2015 02:33 PM

History

#1 Updated by John Diamond almost 5 years ago

First test:

[root@bbpmts bbpmts]# ./bpmcli ct_show_list 0
Description: raw[70222.634506] LXRT releases PID 992 (ID: bpmcli).
 test
Commands: 3
    0:  Immediate       ARM   measurement = raw, trigger = immediate, samples = 1000
    1:   TCLK $26   READOUT   source = raw
    2:   TCLK $26      IDLE   n/a
    3: Empty
    4: Empty

#2 Updated by John Diamond almost 5 years ago

Apparently we don't have an ARM command for the digitizer yet:

[70368.305067] adc250x12xsmod: Control task received unknown message type = 0

See task #9614.

#3 Updated by John Diamond almost 5 years ago

  • % Done changed from 0 to 30

ARM command implemented. Testing shows that the parameters are making it to the digitizer but the raw character devices are not showing reasonable data. Opened a bug ticket to investigate - #9620.

#4 Updated by John Diamond almost 5 years ago

Spent about 2 hours debugging why an incorrect value for the adc250x12xsmod ARM command trigger parameter was being passed to the driver.

#5 Updated by John Diamond almost 5 years ago

Had Peter setup the test rig upstairs to trigger the digitizer and a 500k sine-wave burst at 15Hz. He says we should see a DC signal coming out of the down-converter.

Trying to arm the system for a TBT measurement but it's causing bpmd to crash hard, investigating...

#6 Updated by John Diamond almost 5 years ago

Turn-by-turn test command list:

Description: ddc test
Commands: 3
    0:  Immediate       ARM   measurement = tbt, trigger = external, samples = 3e8
    1:   TCLK $26   READOUT   source = ddc_wide
    2:   TCLK $26      IDLE   n/a
    3: Empty
    4: Empty
    5: Empty

#7 Updated by John Diamond almost 5 years ago

Looks like we were missing support for an external trigger in ADC250X12XS::rtArm(..).

#8 Updated by John Diamond almost 5 years ago

Input signal is 39MHz (matched with the NCO frequency). Couldn't get anything out of the down converter so we went back to testing a raw mode capture. Here's the command list:

[root@bbpmts bbpmts]# ./bpmcli ct_show_list 0
Description: raw[ 7458.336019] LXRT releases PID 1023 (ID: bpmcli).
 test
Commands: 3
    0:  Immediate       ARM   measurement = raw, trigger = external, samples = 1024
    1:   TCLK $26   READOUT   source = raw
    2:   TCLK $26      IDLE   n/a
    3: Empty

And here is the result:
raw mode capture

#9 Updated by John Diamond almost 5 years ago

Also, had to change the primary transform on Z:HRBOOA and Z:HRBOOB from 20 (unsigned data handler) to 10 (float(input)) to get the above plot.

#10 Updated by John Diamond almost 5 years ago

We will probably need Alexei's help getting the DDC to trigger next week...

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