Konica Minolta PCI-1712L user manual channel

Chapter 5

channel.

In this mode, users need to set the clock source and trigger source first, and then generate the output data to be stored in the memory buffers of host PC. The host computer then transfers those data to be written to the DACs from its buffers to the 32K-sample Output FIFO on board. When it detects a trigger, the board outputs the values in the Output FIFO to the DACs at the same time. When the samples in FIFO decreases to less than half size (i.e. 16K samples) of the FIFO, then the card will send a interrupt request to the host PC, which in turn sends 16K samples to the FIFO. This output operation will repeat until either all the data is sent from the buffers or until you stop the operation.

If the two D/A channels are both operating in continuous output mode, the data in FIFO will be sent in an interlaced manner, i.e. The “even” samples in the FIFO are sent to D/A channel 0, while the “odd” samples to D/A channel 1.

qWaveform Output Operation Mode

Waveform output operation mode is a particular and useful application of continuous output operation mode. In this mode, users can output the user-defined waveform pattern repetitively and continuously. Before this operation can begin, users have to use software to allocate the buffer memory and define the waveform pattern first. Then the host computer will transfer the waveform pattern from its buffer allocated in computer memory into the Output FIFO on the board, which in turn will transfer the waveform pattern to the DACs. When the trigger event occurs, each D/A channel running continuous output operation mode will output waveform pattern from FIFO in specific clock rate.

D/A Output Clock Sources

The PCI-1712 can adopt both internal and external clock sources for pacing the analog output of each channel:

wInternal D/A output clock with 16-bit Counter

wExternal D/A output clock that is connected to AO_CLK on the PCLD-8712 screw terminal board

The internal and external D/A output clocks are described in more detail as follows:

qInternal D/A Output Clock

The internal D/A output clock uses a 10 MHz time base. Conversions start on the rising edge of the counter output. Through software to specify the clock source as internal and the clock frequency to pace

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