Fast Memory Capture - DLS-Controls-Private-org/MBF-docs GitHub Wiki

This screen shows the status and configuration of the fast memory capture system.

For direct access to the full memory buffer, see Matlab Fast memory readout for the Matlab interface, or Socket Fast memory readout for the underlying socket API.

All PVs below are prefixed with $(device).

Two graphs are shown at the top:

Title	PV	Description
Channel 0, Channel 1	:MEM:WF0, :MEM:WF1	Window into data captured on channels 0 and 1. The starting point of the window is determined by the :MEM:OFFSET_S field, but for reading large amounts of data the Direct Memory Access API is recommended.

The selection is controlled by three interacting PVs. Data can be captured from ADC, FIR, or DAC data from either axis, and two channels of bunch by bunch data can be captured at any time.

Title	PV	Description
Channel 0, Channel 1	:MEM:SEL0_S, :MEM:SEL1_S	These two PVs allow the channel selection to be configured one channel at a time, but the true selection pattern is shown to the right. These two PVs will rewrite each other as necessary to ensure that the selection is always consistent.
	:MEM:SELECT_S	This is the true selection of which data source will be captured into which channel.

The ADC and DAC sources can be selected, and their control PVs are copied here:

Title	PV	Description
ADC X, ADC Y	:ADC:DRAM_SOURCE_S	Source of ADC data, configured on ADC Setup page.
Fill reject length	:ADC:REJECT_COUNT_S	Length of fill reject filter, configured on ADC Setup page.
DAC X, DAC Y	:DAC:DRAM_SOURCE_S	Source of DAC data, configured on DAC Setup page.

The remaining PVs are used for general control.

Title	PV	Description
View offset	:MEM:OFFSET_S	This programs the start point of the two channel readout waveforms in turns relative to the trigger point.
Runout	:MEM:RUNOUT_S	This configures how much data is captured into memory after a trigger is seen, and can be set to 12.5%, 25%, 50% or 99.5% of the available 2GB. Note that memory capture treats the capture memory as a large circular buffer, and once armed capture continues until a trigger occurs, after which the number of samples configured here are captured.
Capture	:MEM:CAPTURE_S	This initiates an untriggered round of memory capture.
Capture status	:MEM:BUSY	When capture is armed this indicates busy, and indicates Ready when data is captured and ready to be read out.