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DO_PGStart

@ Description

This function performs pattern generation for digital output with the data stored in Buffer at a rate as close to the rate you specified.

@ Cards Support

7300A

@ Syntax

I16 DO_PGStart (U16 CardNumber, void *Buffer, U32 WriteCount, F64 SampleRate)

@ Parameter

CardNumber : The card id of the card that want to perform this operation.
Buffer : The starting address of the memory containing the output data of pattern generation.
           This memory must have been allocated for enough space to store output data.
WriteCount : the number of pattern generation output samples.
SampleRate : The sampling rate you want for digital output in hertz (samples per second). Your maximum rate depends on the card type and your computer system.
                      This argument is only useful if the DO trigger mode was set as internal programmable pacer (TRIG_INT_PACER) by calling DO_7300_Config().

@ Return Code

NoError, ErrorInvalidCardNumber, ErrorCardNotRegistered, ErrorFuncNotSupport, ErrorTransferCountTooLarge
 


Note: Because the scatter-gather mechanism used by PCI7300A, the memory space allocated in your process will be locked before passing the virtual address to the device drivers, and be unlocked after the data acquisition is completed. However, Linux does not give the permission of mlock/munlock to everyone. Only the processes with root privilege can lock/unlock the memory. If your process call this function for PCI7300A_RevA or PCI7300A_RevB, it must have the root privilege.