Omega 1002 manual A/D Conversion, Cpu

4.4 A/D Conversion

An A/D conversion can be initiated three different ways: software command, internal programmable interval timer or external trigger. At the end of the A/D conversion, it is possible to transfer the data by polling a status register and reading the data when ready or by generating a hardware interrupt and an interrupt service routine. All modes are selected by a control register on the OME-PCI-1002 and are supported by the utility software.

Below are key points for successfully collecting A/D data:

zA/D data register, BASE+30h, stores the A/D conversion data.

zA/D data conversion ready register, BASE +10h. Check if A/D data is ready.

zA/D gain control register, BASE+14h, select gain.

zA/D multiplexer control register, BASE+10h, select analog input channel.

zA/D mode control register, BASE+0Ch, select trigger type and transfer type.

zA/D software trigger control register, BASE+1Ch.

zJP1 select single-ended or differential input.

z3 Triggers: Software, Pacer, and External trigger.

z2 Transfer Modes: Polling and Interrupt.

The block diagram is given follows:

	16/8 to 1	Gain	12 bits
CN3	Multi-	Control	A/D	Buffer	Memory
	plexer
	BASE+10h	BASE+14h	Trigger	BASE+30h	CPU
			Logic
			BASE+1Ch
			Software Trigger
OME-PCI-1002H/L

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