Re: realtime performance of adl_pci9118

	Hi,

wicky.zhang napsal(a):
> I have build a test control system which include adlink pci9118dg card, 
> with the matlab/simulink code auto generation function.
>  
> 1: when i run the code generated by matlab/simulink in rtai, i found 
> that the a/d sample rate of single rate is limited to about 33k, if i 
> set it to 50k, system will down.

do you use cmd->flags|=TRIG_WAKE_EOS ?
If yes, then after every sample is generated interrupt and 50 kinterrupts/s
will kill any system.

>   how can i improve it? i hope the system can works at 10k with 5 
> channel of a/d synchronous, is this possible? i can't do the test now 
> because my DAQ card only have

At first, don't measure odd number of the channels, this slow down
driver. So measure 6 channels and ignore data from the one.
If you use TRIG_WAKE_EOS then one channel at 33 k is worse
case that 6 channels at 10 kHz sampling.
Check if the driver uses bus mastering or not. This can you see
in the system logs after driver loading. Message like:
comedi0: adl_pci9118: board=pci9118dg, b:s:f=0:17:0, io=0xd800, 0xd400,
irq=12, bus master.

Michal

Received on 2005-10-13Z08:38:57