Onboard device memory overflow. Labview for PDA error

[EL Zorro]

Im runnin the example for PDA Cont_Acq_Graph_Voltage-Int Clk.vi. But Im getting the following error/
DAQmx Base Read.vi Onboard device memory overflow. Because of system and/or bus bandwith limitations, the driver could not read the data from the device fast enough to keep up with the device troughput. Error code:-200361.
Using IPAQ 5555 pocket pc 2003. No other programs loaded in PDA only this example running in memory. What is wrong?

[cous]

Hi Zorro,

This error indicates that you have written over data in the buffer allocated for the data acquisition before the system could transfer the data from that buffer to system memory. In order to alleviate the error, you could lower the sample rate, increase your buffer size for the acquisition, or change the hardware you are using. I cannot recommend one specific enhancement as I don't know what data acquisition card you are using nor the specifications for your data acquisition (ie. sample rate). Knowing these could help me give you a more certain answer.

Best Regards,
Marcus G.
Applications Engineer
National Instruments

[EL Zorro]

IM using a 6024E PCMCIA DAQ card. I cant get it to work if I try using a scan rate higher than 800 S/s. The board is suppose to handle 200kS/s. 800 S/s is not useful at all. How do you increase the buffer size? THere are now only 5 DAQ functions in the DAQmx base functions. Cant find how to change the buffer size.

[cous]

Hi Zorro,
The maximum scan rate for your acquisition depends on the number of channels that you are trying to sample. E-Series device such as the 6024E only have one multiplexer, so the scan rate must be divided by the number of channels used. This is probably not the issue as you would need to be sampling over 250 channels for 800 S/s to be your maximum sampling rate.
Another limitation may be data processing done during the acquisition. Are you doing any sort of additional data processing, or is the PDA running any other programs while the data acquisition program is running?
Yet another limitation may be the number of samples you transfer from the FIFO to the system memory. Increasing this number will help the acquisition run faster.

If t
hese ideas aren't helpful, please let us know more about your system so we can further resolve your issue.

Best regards,
Marcus G.
Applications Engineer
National Instruments

[EL Zorro]

Im trying to run one of your DAQmxbase examples. Im not running any other application at all.No additional analisys or calculations other than acquiring and displaying the data are being performed. This is the example that continuosly acquires voltage on one channel. The example is set at a scan rate of 100HZ. No other processing is done. What realistic scan rates are you able to use. Can you give me some specific details on PDAs that you tried?