Omega Vehicle Security DAQ-16 user manual CHSL2 CHSL1 CHSL0

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

DMACT - enables the multi-channel DMA capability of the DAQ-16. 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-16's DMA channels is currently active to transfer data. Logic 0 indicates DMA channel 0, logic 1 indicates DMA channel 1.

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.

VALID - when set, logic 1, indicates at least one data sample was lost because it was read by the computer before the next sample was converted. The data was lost because the sampling rate was too fast for the computer to acquire data. VALID is reset by writing to the start conversion register.

CHSL2, CHSL1, CHSL0 - select the multiplexer channel for the analog input signal.

CHSL2

CHSL1

CHSL0

MUX channel

0

0

0

channel 0

0

0

1

channel 1

0

1

0

channel 2

0

1

1

channel 3

1

0

0

channel 4

1

0

1

channel 5

1

1

0

channel 6

1

1

1

channel 7

DAQ-16 Users Manual

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Contents 15,1*,1 WARRANTY/DISCLAIMER Servicing Europe Servicing North AmericaFor immediate technical or application assistance Page Application of Council Directive Manufacturers NameManufacturers Address Standards to which Conformity is DeclaredTable of Contents List of Figures and Tables Installation IntroductionDAQ-16 Specifications Analog to Digital Converter Maximum Input Voltage Amplifier RangeJumper J7 Configuration Volt range Unipolar Bipolar Binary 2s complement Voltage Binary ’s Complement Digital to Analog Converters Unipolar Digital Input/OutputChannel Bipolar Gain =Base Address I/O Base Address SelectionClock Selection Internal Clock External Clock Trigger Selection Start of ConversionDirect Memory Access 10. Jumpers J8 and J9 ConfigurationInterrupts External InterruptExternal Connections Page Register Description Control Word RegisterCHSL2 CHSL1 CHSL0 3 DAC0 Register Multi-Function Timer RegisterStart of Conversion Register 4 DAC1 RegisterProgramming the 8254 Counter/Timer Counter 1 Clock rate register high word Version January 28