Omega Engineering OME-A8111 manual Counter, 2 A/D Input Buffer Register

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2.4.1The 8254 Counter

The 8254 Programmable timer/counter has 4 registers from Base+0 through Base+3. For detailed programming information about the 8254, please refer to Intel‘s “Microsystem Components Handbook”.

Address	Read	Write
Base+0	8254 Counter 0	8254	Counter 0
Base+1	8254 Counter 1	8254	Counter 1
Base+2	8254 Counter 2	8254	Counter 2
Base+3	Reserved	8254	Counter Control

2.4.2A/D Input Buffer Register

(READ)	Base+4: A/D Low Byte Data Format
Bit 7	Bit 6	Bit 5	Bit 4	Bit 3	Bit 2	Bit 1	Bit 0
D7	D6	D5	D4	D3	D2	D1	D0
(READ)	Base+5: A/D High Byte Data Format
Bit 7	Bit 6	Bit 5	Bit 4	Bit 3	Bit 2	Bit 1	Bit 0
0	0	0	READY	D11	D10	D9	D8

A/D 12 bit data: D11…..D0, D11 = MSB, D0 = LSB

READY = 1: A/D 12 bits data not ready

= 0: A/D 12 bits data is ready

The low 8 bits of A/D data are stored in address BASE+4 and the high 4 bits of data are stored in address BASE+5. The READY bit is used as an indicator for A/D conversion.

When a A/D conversion is completed, the READY bit will be cleared to zero (Low).

OME-A-8111 Hardware Manual (ver.1.1, Jul/2003)

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Contents User’sGuide Benelux CanadaMexico Czech RepublicOME-A-8111 Table of Contents Calibration Features General DescriptionAnalog Inputs SpecificationsPower Consumption 3 A/D ConverterInterrupt Channel DA ConverterDigital I/O Applications Programmable Timer/CounterProduct Check List Hardware Configuration Board Layout I/O Base Address Setting Default base address isJumper Setting 1 JP1 D/A Internal Reference Voltage SelectionI/O Register Address Address Read Write8254 Counter 2 A/D Input Buffer Register3 D/A Output Latch Register 4 D/I Input Buffer RegisterClear Interrupt Request 6 A/D Gain Control Register7 A/D Multiplex Control Register 8 A/D Mode Control Register SI2 SI1 SI09 A/D Software Trigger Control Register 10 D/O Output Latch Register Digital I/O CN38254 Timer/Counter CounterA/D Conversion Sec1 A/D conversion flow If switching from one channel to the next secPacer Trigger Mode 2 A/D Conversion Trigger ModesUsing software trigger and polling transfer 3 A/D Transfer ModesD/A Conversion Analog Input Signal Connection Signal ShieldingPin Assignment CN1 Analog input/Analog output/Connect Pin AssignmentCN2 Analog input/Analog output/Connect Pin Assignment CN3 Analog input/Analog output/Connect Pin AssignmentOME-DB-16P Daughter BoardOME-CA-4002 OME-DB-16RCalibration Calibration VR DescriptionA/D Calibration Steps DI/O TestingD/A Calibration Steps WARRANTY/DISCLAIMER Temperature