Omega Engineering DAQ-12 user manual INT2 INT1 INT0 Description

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INT2, INT1 and INT0 control the DAQ-12 interrupt source.

INT2

INT1

INT0

DESCRIPTION

0

0

0

Interrupt disabled

1

0

0

Interrupt timer 2

1

0

1

Interrupt on terminal count

1

1

0

External interrupt

1

1

1

Interrupt on end of conversion

DMAEN - enables / disables DMA. When set, logic 1, DMA transfers are enabled.

DMACT - enables the multi-channel DMA capability of the DAQ-12. When set, logic 1, a terminal count on the active DMA channel causes DMA transfers to begin on the "stand-by" channel. When cleared, logic 0, DMA transfers halt when the terminal count is reached on the active channel.

DMACH - indicates which of the DAQ-12'S DMA channels is currently active to transfer data. Logic 0 indicates DMA channel 0, logic 1 indicates DMA channel 1.

DMASL - When using differential input mode, eight input channels are available (CH0+ through CH7+). When using single-ended inputs, 16 channels are available (CH0+ through CH15+). The first eight channels are input through the connections marked CH0+ through CH7+ and the second eight channels through CH0- through CH7-.

LEVEL - selects the edge of the external trigger input. When set, logic 1, A/D conversions will begin on the falling edge of the external trigger input. When cleared, logic 0, conversions will begin on the rising edge of the external trigger. IMPORTANT: LEVEL must be logic 0 when internal triggering is used.

TRIG - selects between internal and external triggers. When set, logic 1, the external trigger is selected.

CLK - selects between internal and external clock sources. When set, logic 1, the external clock source is selected.

RUN - when set, logic 1, the A/D converter is placed in the 'run' mode and will begin converting data when a trigger is received. RUN may be cleared at any time by writing a "0" to it. When using DMA transfers, RUN is automatically cleared when a terminal count is received with DMACT set to "0".

EOC - when set, indicates an end of conversion has taken place and the data is available in the A/D converter data register.

DAQ-12 Users Manual

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Contents 15,1*,1 WARRANTY/DISCLAIMER Application of Council Directive Manufacturers NameManufacturer’s Address Standards to which Conformity is DeclaredServicing Europe Servicing North AmericaFor immediate technical or application assistance Page Table of Contents Introduction List of Figures and Tables Installation DAQ-12 Specifications Jumper J1 Configuration Analog to Digital ConverterDisable Pre-Scaler Enable Pre-Scaler Factory default Recommended Input Ranges and Gain Settings Code Digital to Analog Converters Voltage Unipolar Bipolar CodeChannel Bipolar Gain =Digital Input/Output Base AddressClock Selection Internal Clock External Clock Trigger Selection Start of ConversionDirect Memory Access 10. Jumpers J8 and J9 Configuration DackInterrupts External InterruptExternal Connections Page Register Description Control Word RegisterINT2 INT1 INT0 Description Start of Conversion Register 3 A/D Converter Data Register5 D/A Converter 1 Register Multi-Function Timer Register4 D/A Converter 0 Register Clock Rate Register low wordProgramming the 8254 Counter/Timer Counter 1 Clock rate register high word Version January 28