Omega OME-A822PG manual Using software trigger and polling transfer, Refer to Sec

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2.7.4Using software trigger and polling transfer

If the user needs to control the A/D converter without the A-822 software driver, software trigger and polling transfer is suggested. The program steps are listed below:

1.send 0x01 to the A/D mode control register (software trigger + polling transfer)

(refer to Sec. 2.4.8)

2.send channel number to the multiplexer control register (refer to Sec. 2.4.7)

3.send the gain control code value to the gain control register (refer to Sec 2.4.6)

4.delay the settling time (refer to Sec. 2.4.6 and Sec. 2.4.7)

5.send any value to the software trigger control register to generate a software trigger signal

(refer to Sec. 2.4.9)

6.scan the READY bit of the A/D high byte data until READY=0 (refer to Sec. 2.4.2)

7.read the 12 bit A/D data (refer to Sec. 2.4.2)

8.convert the 12 bit binary data to a floating point value

OME-A-822PGL/PGH Hardware Manual ---- 30

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Contents User’sGuide Canada MexicoBenelux Czech RepublicOME-A-822PGH/PGL Tables of Contents IntroductionConnector Features General DescriptionSpecifications Power ConsumptionAnalog Inputs 3 A/D ConverterInterrupt Channel DA ConverterDigital I/O Programmable Timer/Counter Direct Memory Access Channel DMAApplications Product Check ListHardware Configuration Board LayoutI/O Base Address Setting Default base address isJumper Settings 1 JP1 D/A Internal Reference Voltage Selection2 JP2 D/A Int/Ext Ref Voltage Selection 3 JP3 Single-ended/Differential Selection4 JP4 A/D Trigger Source Selection 5 JP5 Interrupt Level Selection6 JP6 User Timer/Counter Clock Input Selection 7 JP7 DMA Dack Selection JP8 DMA DRQ Selection DRQ JP7 Dack JP8 DMAI/O Register Address Address Read WriteConversion is completed, the Ready bit will clear to zero 1 8254 Counter2 A/D Input Buffer Register 3 D/A Output Latch Register 4 D/I Input Buffer Register Clear Interrupt Request6 A/D Gain Control Register GAIN3 GAIN2 GAIN1 GAIN0OME-A-822PGH Gain Control Code Table 7 A/D Multiplex Control Register8 A/D Mode Control Register 9 A/D Software Trigger Control Register 10 D/O Output Latch Register Digital I/O CN28254 Timer/Counter CounterA/D Conversion 1 A/D conversion flow Polling, interrupt and DMA2 A/D Conversion Trigger Modes 3 A/D Transfer ModesRefer to Sec Using software trigger and polling transferDelay the settling time refer to Sec .4.6 and Sec D/A Conversion Analog Input Signal Connection OME-A-822PGL/PGH Hardware Manual OME-A-822PGL/PGH Hardware Manual Signal Shielding Use a single connection to frame ground not A.GND or D.GNDUsing OME-DB-8225 CJC Output CN2 Digital Output Pin Assignment CN1/CN2/CN3 Pin AssignmentCN1 Digital Input Pin Assignment SINGLE-ENDED Signal Mode Differential Signals Daughter Board OME-DB-8225OME-DB-37 OME-DB-16PCalibration Description of Variable ResistorsD/A Calibration A/D Calibration Diagnostic Utility IntroductionOME-A-822PGL/PGH Hardware Manual Running The Diagnostic Utility Setup Base address selection screenDMA no and IRQ no selection screen Calibration Function Test Test Test Screen Digital I/O Test Screen Multiplexer Test Screen Use IRQ Test Screen Use DMA Test Screen DA Gain Test Screen Timer 0 Test Screen Special Test Help WARRANTY/DISCLAIMER Temperature