Omega Engineering PCI-DAS1200 manual BADR2, Adc Data Register, Adc Fifo Clear Register

7.4 BADR2

The I/O Region defined by BADR2 contains the ADC Data register and the ADC FIFO clear

register.

7.4.1 ADC DATA REGISTER

BADR2 + 0

ADC Data register.

WRITE

Writing to this register is only valid for SW initiated conversions. The ADC Pacer source must be set to 00 via the ADPS[1:0] bits. A null write to BADR2 + 0 will begin a single conversion. Conversion status may be determined in two ways. The EOC bit in BADR1 + 0 may be polled

until true or ADNEI (the AD FIFO not-empty interrupt) may be used to signal that the ADC conversion is complete and the data word is present in the FIFO.

READ

15	14	13	12	11	10	9	8	7	6	5	4	3	2	1	0
0	0	0	0	AD11	AD10	AD9	AD8	AD7	AD6	AD5	AD4	AD3	AD2	AD1	AD0
				MSB											LSB

AD[11:0] This register contains the current ADC data word. Data format is dependent upon offset mode:

Bipolar Mode: Offset Binary Coding

000 h = -FS

7FFh = Mid-scale (0V)

FFFh = +FS - 1LSB

Unipolar Mode: Straight Binary Coding

000 h = -FS (0V)

7FFh = Mid-scale (+FS/2)

FFFh = +FS - 1LSB

7.4.2 ADC FIFO CLEAR REGISTER

BADR2 + 2

ADC FIFO Clear register. A Write-only register. A write to this address location clears the ADC FIFO. Data is don't care. The ADC FIFO should be cleared before all new ADC operations.

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