@M4DAC16 Class

Requirements

• needs https://github.com/razanskylab/BaseHardwareClass to work

Card used for programming and in example

• Installed memory: 4096 MByte
• Max sampling rate: 250.0 MS/s
• Channels: 2
• Kernel Version: 5.1 build 15353
• Library Version: 5.6 build 15415

FiFo Notes

• speed depends on the selected notification size as a small notify size generates very many interrupts and status reads that disturbs the continuous data transfer
• For performance reasons buffer size = 4 * Notifysize

Real Life FiFo testing (using Spectrum Control Software)

• PCI Express interface: Gen2 with 4 lanes. Max Payload: 128 Byte
  • Notifysize: 16 kiB Read 431.8 MiB/s (452.8 MB/s)
  • Notifysize: 32 kiB Read 1061.0 MiB/s (1112.5 MB/s)
  • Notifysize: 64 kiB Read 1242.0 MiB/s (1302.3 MB/s)
  • Notifysize: 128 kiB Read 1575.1 MiB/s (1651.7 MB/s)
  • Notifysize: 256 kiB Read 1578.1 MiB/s (1654.8 MB/s)
  • Notifysize: 512 kiB Read 1581.3 MiB/s (1658.1 MB/s)
  • Notifysize: 1024 kiB Read 1573.1 MiB/s (1649.5 MB/s)
• above Notifysize 128 kiB no real speed increase...
• notifysize might become important again as soon as Matlab gets involved...

OA + PD data transfer examples

• we record 2048 - 8,192 Bytes per trigger event)
  • 16 bit samples, i.e. 2 Bytes per sample
  • 512 - 2048 samples per channel
  • 2 channesl (we crop later, does not matter here)
• we record at an absolute max. prf of 20 kHz
• total max. required transfer rate is 163.84 MB/s (8,192 Bytes * 20 kHz), i.e. factor 10 safety margin!

Notes