Digi BL1800 user manual Void digOutint channel, int value

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void digOut(int channel, int value);

sets the state of a digital output bit. jrioInit must be called first.

channel is the output channel number (0-3 on the Jackrabbit). value is the output value (0 or 1).

void digOn(int channel);

sets the state of a digital output bit to on (1). jrioInit must be called first.

channel is the output channel number (0–3 on the Jackrabbit).

void digOff(int channel);

sets the state of a digital output bit to off (0). jrioInit must be called first.

channel is the output channel number (0–3 on the Jackrabbit).

NOTE: See the sample program JRIOTEST.C for an example of using the digital out- put functions.

4.4.1.3 Analog Output

The two analog output channels on the Jackrabbit (DA0 and DA1 on header J5) are con- trolled by a pulse-width modulation (PWM) driver. This requires the use of some fraction of the CPU cycles when the driver is running (up to 20% when both D/A channels are used). A voltage is selected by giving a value from 0 to 1024 to the driver, corresponding roughly to 0.1 V to 3.5 V on DA0. Because of the PWM interrupt frequency, the PWM driver can provide a continuous range of voltage output in the range from 0.1 V to 3.0 V for DA0, and 0.6 V to 3.6 V for DA1. These ranges can be specified with the constants PWM_MIN, PWM_MAX0, and PWM_MAX1. In other words, setting channel DA0 to the value PWM_MIN will output 0.1 V, and setting it to PWM_MAX0 will output 3.0 V. Similarly, set- ting DA1 to PWM_MIN will output 0.6 V, and setting it to PWM_MAX1 will output 3.6 V. Val- ues below PWM_MIN will be rounded down to 0, and values above PWM_MAX0 (PWM_MAX1 for DA1) will be rounded up to 1024.

The output channels can also be set in an “always on” or “always off” mode, which does not require CPU cycles. The “always on” mode is set by requesting an output value of 1024, and will provide about 3.4 V on channel DA0, and 3.6 V on DA1. The “always off” mode is selected by asking for a value of 0, and provides an output of around 0.1 V on DA0 and 0.0 V on DA1.

See Table 5 for a summary of the possible analog output voltages corresponding to values given in the anaOut function.

52	Jackrabbit (BL1800)

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Contents Jackrabbit BL1800 Programmable Single-Board ComputerTrademarks Digi International IncTable of Contents Index Schematics Features IntroductionJackrabbit Features Development and Evaluation ToolsOnline Documentation How to Use This ManualAdditional Product Information Emissions CE ComplianceImmunity Interfacing the Jackrabbit to Other Devices SafetyDesign Guidelines General Jackrabbit BL1800 Development Kit Contents Getting StartedDevelopment Hardware Connections Board Attach Jackrabbit to Prototyping BoardConnect Programming Cable Assemble AC AdapterConnect Power Installing Dynamic C Troubleshooting Run a Sample ProgramTechnical Support Where Do I Go From Here?Real-Time Clock Subsystems BL1800Jackrabbit Pinouts HeadersDigital Inputs/Outputs Digital InputsDigital Outputs HV3 Sourcing OutputConfigurable High-Current Output Bidirectional I/O Changing HV3 to a Sinking OutputSchematic Diagram of A/D Converter A/D ConverterJackrabbit BL1800 Schematic Diagram of D/A Converters D/A ConvertersV ⋅ 1 e RC 1 DA1Typical DA1 Voltages for Various Duty Cycles 2 DA0 Typical DA0 Voltages for Various Duty CyclesUser’s Manual 2 RS-485 Serial Communication1 RS-232 Ground recommended Programming Port 485 R16User’s Manual Changing Between Program Mode and Run Mode Programming CableFlash Eprom MemorySram Clock Doubler Other HardwareExternal Interrupts Spectrum Spreader Jackrabbit BL1800 Software Reference An Overview of Dynamic CJackrabbit BL1800 Sample Programs Jackrabbit Sample ProgramsDEMOJR1.C Sample Program DEMOJR1.CSingle-Stepping Watch Expression Break PointWatching Variables Dynamically Summary of FeaturesEditing the Program User’s Manual Other Sample Programs Illustrating Digital I/O R/W pin and DB0-DB3 on 3 RS-232 Serial Communication Sample Programs 4 RS-485 Serial Communication Sample Program Cooperative Multitasking Int vswitch Advantages of Cooperative Multitasking Jackrabbit Function Calls 1 I/O DriversVoid digOutint channel, int value Void anaOutint channel, int value Void anaInint channel, int *value Serial Communication Drivers Add-On Modules Upgrading Dynamic CPatches and Bug Fixes Appendix A. Specifications Electrical and Mechanical Specifications Figure A-1shows the mechanical dimensions for the JackrabbitTable A-1. Jackrabbit Board Specifications Exclusion Zone Exclusion ZonesFigure A-3. User Board Footprint for Jackrabbit Jumper Configurations Figure A-4. Location of Jackrabbit Configurable PositionsTable A-2. Jackrabbit Jumper Configurations Conformal Coating Conformally coated areaUse of Rabbit 2000 Parallel Ports JackrabbitTable A-3. Jackrabbit Pinout Configurations PD0 PD1 Jackrabbit BL1800 Appendix B. Prototyping Board Jackrabbit Connectors User LEDs Buzzer Prototyping Board OverviewPrototyping Board Features Mechanical Dimensions and Layout Top SideUsing the Prototyping Board Top SideDemonstration Board RelayExisting Prototyping Board Top SidePE0 VCC HV0 SM1 SM0 HV2 Stat Jackrabbit BL1800 Appendix C. Power Management Power SuppliesDcin Current mA Batteries and External Battery Connections 950 mA·h = 5.4 years 20 µABattery Backup Circuit Figure C-5shows the Jackrabbit battery backup circuitryPower to Vram Switch Reset GeneratorFigure C-7shows a schematic of the chip select circuit Chip Select CircuitJackrabbit BL1800 Index SMODE0 SMODE1RABDB01.C RABDB02.C Schematics