ADLINK PCI-9810 - Manual (Page 51)

Operation Theory 39
Total Data Throughput
When four channels start simultaneously, the total data throughput
from the AD converter to the onboard FIFO memory is:
Sampling Rate x number of channels x 2 bytes/channel
Therefore, the maximum total data throughput is 160 Mbytes/sec.
160MB/s = 20MHz x 4 channels x 2 bytes/channel
This extremely high data rate is beyond the 32-bit/33 MHz PCI bus
bandwidth. To address this two 16K words (samples) FIFO are
designed to buffer the data.
A total of 32K word (32K samples) is used when FIFO is onboard.
When four channels are used, the FIFO size is 8K samples per
channel. When two channels (#0 and #1) are used, the FIFO size
is 16K samples per channel. When only one (#0) is used, the FIFO
size is 32K samples.
You need to calculate the total data throughput for your
applications, as this value would be relative to the total data length
that can be continuously acquired.
Maximum Acquiring Data Length
The burst PCI bandwidth is 132 MB/s. However, the effective
sustained data rate is usually less than 100 MB/s. This value may
even be lower when additional PCI devices are used
simultaneously. If the total AD data throughput is lower than the
PCI bandwidth, the AD data can be stored into the host memory
through bus-mastering DMA and the total acquiring data length
could be up to 64 MB (32M samples) which is the PCI controller’s
maximum. If the total AD data throughput is higher than the PCI
bandwidth, the maximum data length will either be 16K or 8K
samples, which is the maximum length from the size of onboard
FIFO.