Analog I/O Wildcard User Guide

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The constants that are associated with the DAC output channels are DAC12_CH0, DAC12_CH1, DAC12_CH2, DAC12_CH3, DAC12_CH4, DAC12_CH5, DAC12_CH6, and DAC12_CH7. To output a voltage on channel DAC 0 (pin 24 on the Field Header), use the function To_DAC as shown in Listings 1-1 and 1-2.

Listing 1-1 C Code Listing for outputing 2.000 votls to Channel 0 on Module 0.

#include <\mosaic\allqed.h>	// include all qed utilities
#include "library.c"	// be sure to include kernel ext
#define ANALOG_MODULE0 0	// define current module
void main ( void )
{
Init_Analog_IO(INT_2V_DAC12,ANALOG_MODULE0);	// init DAC to use 2.048 int ref
To_DAC12( 2000, DAC12_CH0, ANALOG_MODULE0);	// output 2.000 volts to ch 0
}

Listing 1-2 Forth Code Listing for outputing 2.048 volts to Channel 0 on Module 0

DECIMAL	\ set base to decimal
0 CONSTANT ANALOG_MODULE0	\ define current module
INT_2V_DAC12 ANALOG_MODULE0 Init_Analog_IO	\ init DAC to use 2.048 internal ref
2000 DAC12_CH0 ANALOG_MODULE0 To_DAC12	\ output 2.000 volts to channel 0

Another useful function, named To_All_DACs, simultaneously outputs a single 12-bit value to all DAC channels on a specified module. To_All_DACs uses the primitives Delay_Update_DAC12 and Update_DAC12 to simultaneously output the specified value to all channels. Listings 1-3 and 1-4 demonstrate how to use the Delay_Update_DAC12 and Update_DAC12 functions to simultaneously write a stair-step pattern to all eight output channels of a DAC.

Listing 1-3 C Code Listing for using Delay_Update_DAC12 and Update_DAC12.

#include <\mosaic\allqed.h>	// include all qed utilities
#include "library.c"	// be sure to include kernel ext
#define ANALOG_MODULE0 0	// define current module
void main ( void )
{
Init_Analog_IO(INT_2V_DAC12,ANALOG_MODULE0);	// init DAC to use 2.048 int ref
Delay_Update_DAC12( ANALOG_MODULE0 );	// delay DAC update
To_DAC12( 0500, DAC12_CH0, ANALOG_MODULE0);	// output 0.5 volts to ch 0
To_DAC12( 1000, DAC12_CH1, ANALOG_MODULE0);	// output 1.0 volts to ch 1
To_DAC12( 1500, DAC12_CH2, ANALOG_MODULE0);	// output 1.5 volts to ch 2
To_DAC12( 2000, DAC12_CH3, ANALOG_MODULE0);	// output 2.0 volts to ch 3
To_DAC12( 2500, DAC12_CH4, ANALOG_MODULE0);	// output 2.5 volts to ch 4
To_DAC12( 3000, DAC12_CH5, ANALOG_MODULE0);	// output 3.0 volts to ch 5
To_DAC12( 3500, DAC12_CH6, ANALOG_MODULE0);	// output 3.5 volts to ch 6
To_DAC12( 4000, DAC12_CH7, ANALOG_MODULE0);	// output 4.0 volts to ch 7
Update_DAC12( ANALOG_MODULE0 );	// simultaneously update all dacs
}

Listing 1-4 Forth Code Listing for using Delay_Update_DAC12 and Update_DAC12.

DECIMAL	\ set base to decimal
0 CONSTANT ANALOG_MODULE0	\ define current module
: STAIR_STEP ( -- )
INT_2V_DAC12 ANALOG_MODULE0 Init_Analog_IO	\ init DAC to use 2.048 int ref
ANALOG_MODULE0 Delay_Update_DAC12	\ delay DAC update
0500 DAC12_CH0 ANALOG_MODULE0 To_DAC12	\ output 0.5 volts to channel 0
1000 DAC12_CH1 ANALOG_MODULE0 To_DAC12	\ output 1.0 volts to channel 1
1500 DAC12_CH2 ANALOG_MODULE0 To_DAC12	\ output 1.5 volts to channel 2
2000 DAC12_CH3 ANALOG_MODULE0 To_DAC12	\ output 2.0 volts to channel 3
2500 DAC12_CH4 ANALOG_MODULE0 To_DAC12	\ output 2.5 volts to channel 4
3000 DAC12_CH5 ANALOG_MODULE0 To_DAC12	\ output 3.0 volts to channel 5
3500 DAC12_CH6 ANALOG_MODULE0 To_DAC12	\ output 3.5 volts to channel 6
4000 DAC12_CH7 ANALOG_MODULE0 To_DAC12	\ output 4.0 volts to channel 7
ANALOG_MODULE0 Update_DAC12	\ simultaneously update all dacs
;

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Analog I/O Wildcard User Guide