Standard Library

These standard library functions are built in natively into the firmware and are available on all systems. You will likely not use these directly, but use the simpler wrapper methods provided by the individual modules.

tip

These are particularly useful for using microcomputers or or for making custom modules.

caution

Unless otherwise is stated, all Standard Libraries that calls for array require a byte array and not a float array. Use b1 for example instead of a1.

Special Pins

Some functions only work on pins with specific features.

Analog capable pins: P1, P2, P3, P4, P5, P6, P7, P8, P9, P17
Interrupt capable pins: P1, P2, P3, P4, P5, P6, P7, P12
PWM capable pins: P1, P2, P3, P4, P5, P6, P7, P8, P11

tip

PWM pins share timers. Changing the frequency on one will effect the other. Changing duty-cycle is okay however!

P1, P2
P3
P4, P11
P5, P6, P7, P8

Print

Print to output.

Function	Description
`Print("text" or variable)`	Print the value of its argument.
`PrintLn("text" or variable)`	Print the value of its argument with line breaks.

Print() accepts multiple argument, separated by commas, Print("Value is: ", _v)

tip

Print is invoked automatically when a function returns a value that is not consumed. Running DRead(1, 1) in immediate mode will show 0 or 1.

Hosted-Language Samples

Python
JavaScript
.NET
Arduino

Start by setting up for Python or MicroPython.

duelink.print("Hello World!")

duelink.printLn("Hello World!")

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//code

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//code

Start by setting up for Arduino or C++.

//code

Timing

Function	Description
`Wait(duration)`	Wait for `duration` milliseconds.
`TickMs()`	Read system ticks in milliseconds.
`TickUs()`	Read system ticks in microseconds.

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Arduino

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duelink.System.GetTickMicroseconds()

duelink.System.GetTickMilliseconds():

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//code

Start by setting up for .NET.

//code

Start by setting up for Arduino or C++.

//code

Pin Control

Stat LED

Control the on-board STAT LED, found on every single DUELink module.

Function	Description
`statled(high, low, count)`	Blink the status (STAT) LED with `high` duration on in milliseconds and `low` duration in milliseconds. Repeat `count`, use -1 to repeat forever.

Hosted-Language Samples

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Arduino

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#Blink the STAT LED on for 1000 milliseconds, off for 1000 milliseconds, 10 times. 
duelink.System.StatLed(1000, 1000, 10)

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//Blink the STAT LED on for 1000 milliseconds, off for 1000 milliseconds, 10 times. 
await duelink.System.StatLed(1000, 1000, 10);

Start by setting up for .NET.

//Blink the STAT LED on 1000 milliseconds, off 1000 milliseconds, 10 times. 
duelink.System.StatLed(1000, 1000, 10);

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//code

Digital

Access digital pins.

Function	Description
`DRead(pin, pull)`	Return the digital state of `pin`. Enable `pull`: 0 = none, 1 = up, 2 = down.
`DWrite(pin, state`)	Set `pin` to `state`: 1 = high or 0 = low.

Hosted-Language Samples

Python
JavaScript
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Arduino

Start by setting up for Python or MicroPython.

# Read pin 2 level with pull up
x = duelink.Digital.Read(2, 'PullUp')
print(x)
# Set pin 1 high
duelink.Digital.Write(1, True)

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// Read pin 2 level with pull up
duelink.Digital.Write(2, 'PullUp');
print(x)
// Set pin 1 high
duelink.Digital.Write(1, True)

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// Read pin 2 level with pull up
duelink.Digital.Write(2, 'PullUp');
print(x);
// Set pin 1 high
duelink.Digital.Write(1, True);

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//code

Analog

Access pins in their analog format.

Function	Description
`VRead(pin)`	Read calibrated voltage level on `pin`.
`PWrite(pin, power)`	Set `power` level on `pin` using PWM. Power level is 0 to 1, 0.33 is 33% for example.

VRead() only works with analog capable pins, see Special Pins. PWrite() only works on PWM pins, see Special Pins.

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duelink.analog.PowerWrite(pin, dutycycle)

duelink.analog.VoltageRead(pin)

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//code

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//code

Start by setting up for Arduino or C++.

//code

Beep

Generate tones. This is a blocking function that works on all pins.

Function	Description
`Beep(pin, frequency, duration)`	Generate a beep on `pin` with `frequency` for `duration` in milliseconds.

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# Play frequency 256 on pin 0 for 1000 milliseconds.
duelink.Sound.Beep(pin: int, frequency: int, duration: int)

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// Play frequency 256 on pin 0 for 1000 milliseconds.
await duelink.Beep(0, 256, 1000)

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// Play frequency 256 on pin 0 for 1000 milliseconds.
duelink.Beep(0, 256, 1000);

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//code

Melody

Generate tones. This is a non-blocking function that works on PWM pins.

Melody() requires a float array, use a1 for example. Float arrays must be initialized with {} brackets.

Function	Description
`MelodyP(pin, {notes})`	A non blocking call to play a melody in the background on `pin` using the frequencies and delays found in `notes`.
`MelodyS(pin)`	A non blocking call to stop a melody in the background on `pin`.

Use a float array for notes.

Dim a1[]={500, 50, # 500Hz for 50ms
        1000, 100} # 1000Hz for 100ms
Melody(1, a1)

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duelink.Sound.MelodyPlay(pin:int, notes: float[])

duelink.Sound.MelodyStop(pin:int)

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//code

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//code

Start by setting up for Arduino or C++.

//code

Button

Use interrupts to keep track of pins. Only available on interrupt capable pins, see Special Pins above!

Function	Description
`BtnEn(pin, enable, pull)`	Enable button scanning feature on `pin` with `pull` set to 0: no pull, 1: pullup, 2: pulldown. `enable`: 1 = Enable 0 = Disable.
`BtnUp(pin)`	`pin`: Returns 1 if `pin` transitioned to high level.
`BtnDown(pin)`	`pin`: Returns 1 if `pin` transitioned low.

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duelink.Button.IsValid(pin: int)

duelink.Button.Enable(pin: int, enable: bool)

duelink.Button.Up(pin: int)

duelink.Button.Down(pin: int)

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Start by setting up for .NET.

Start by setting up for Arduino or C++.

//code

Frequency

Sets a frequency (PWM) parameters to a pin. Only works on pins that support PWM.

Function	Description
`Freq(pin, frequency, duration, dutycycle)`	Set PWM `pin` to `frequency` for `duration` in milliseconds at `dutycycle` where 1 is 100%, 0.2 is 20%...etc.

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duelink.Frequency.Set(pin: int, frequency, duration_ms=0, dutycyle=50)

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Start by setting up for .NET.

Start by setting up for Arduino or C++.

//code

Touch

Read capacitive touch by charging a pin and then reading the discharge time in microseconds.

Function	Description
`Touch(pin, charge_t, charge_s, timeout)`	Charges `pin` with charge state `charge_s` for charge time `charge_t` in milliseconds then read how long it takes for pin to discharge, returning value in microseconds. `timeout` is used in case the pin didn't change its state.

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duelink.Touch.Read(pin: int, charge_t: int, charge_s: int, timeout: int)

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//code

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//code

Start by setting up for Arduino or C++.

//code

Digital Control

Distance

Read distance from ultrasonic distance sensors.

Function	Description
`Dist(trig, echo)`	Returns distance in centimeters from ultrasonic distance sensor connected to `trig` and `echo` pins.

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duelink.DistanceSensor.Read(trigPin, echoPin)

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//code

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//code

Start by setting up for Arduino or C++.

//code

Servo Motors

Control servo motors.

Function	Description
`ServoSt(pin, degree)`	Position a servo on `pin` to `degree`: 0 to 180

ServoSt() only works with PWM pins, see Special Pins.

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duelink.Servo.Set(pin, position)

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//code

Start by setting up for .NET.

//code

Start by setting up for Arduino or C++.

//code

I2C

Access the I2C bus.

Function	Description
`I2cCfg(baudrate)`	`baudrate`: Set the I2C clock speed in khz, typically 100K or 400K, and 1M in some cases.
`I2cWr(address, [arrayWrite], [arrayRead])`	`address`: I2C slave address (7 bits) - `arrayWrite`: array to send, `arrayRead`: array to read.

Pins used for I2C are 15-SCL and 16-SDA.

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duelink.I2C.Write(address: int, data: bytes, offset: Optional[int] = 0, length: int = None)

duelink.I2C.Read(address: int, data: bytearray, offset: Optional[int] = 0, length: int = None)

duelink.I2C.Configuration(self, baudrate)

duelink.I2C.WriteRead(self, address: int, dataWrite: Optional[bytes], countWrite: int, dataRead: Optional[bytearray], countRead: int)

Start by setting up for JavaScript.

//code

Start by setting up for .NET.

//code

Start by setting up for Arduino or C++.

//code

SPI

Access the SPI bus.

Function	Description
`SpiCfg(mode, frequency)`	Configure SPI with `mode`: 0 to 3 and `frequency` in KHz, ranging 200KHz to 20MHz
`SpiWr(byte)`	Write a `byte` then return the received byte.
`SpiWrs([data_w], [data_r])`	Write an byte array of `data_w` , also return an byte array of `data_r`.

tip

The system defaults to SpiCfg(0,8000)

Pins used for SPI are 12-SCK, 13-MISO, 14-MOSI. Use any GPIO for manual use of CS.

Hosted-Language Samples

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duelink.Spi.Configuration(mode, frequency)

duelink.Spi.WriteByte(data: int)

duelink.Spi.WriteRead(dataWrite: Optional[bytes], dataRead: Optional[bytes]) 

Start by setting up for JavaScript.

//code

Start by setting up for .NET.

//code

Start by setting up for Arduino or C++.

//code

Serial (UART)

Read and write serial data.

Function	Description
`SerCfg(baud, rxsize)`	Start serial port with `baud` and allocate a receive buffer of `rxsize`.
`SerRd()`	Read a single byte from the receive buffer. Returns zero if it finds no data.
`SerRds([data], timeout)`	Block the system till all data elements are filled. Terminate and return if no data received in `timeout` milliseconds. Returns how many bytes it read successfully.
`SerWr(byte)`	Write a single `byte` to the serial port.
`SerWrs([data])`	Write an array of `data`.
`SerB2R()`	Return how many bytes are available in the receive buffer.
`SerDisc()`	Discard the receive buffer.

The pins used for UART are 1-RX, 2-TX, 3-DBG. The DBG pin is an output indicating the sample point, used by us internally.

Serial is handled by software with special internal features. There is also basic hardware UART option available when UART upstream is not needed, for example on boards with only USB upstream, such as DueDuino. To activate the hardware UART, use a negative baud in SerCfg(), for example SerCfg(-115200,100). Pins used for hardware UART are 21-TX and 22-RX. We do not support using both hardware and software UARTs simultaneously.

Hosted-Language Samples

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Arduino

Start by setting up for Python or MicroPython.

duelink.Uart.Enable(baudrate)

duelink.Uart.Write(data)

duelink.Uart.BytesToRead()

duelink.Uart.Read()

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//code

Start by setting up for .NET.

//code

Start by setting up for Arduino or C++.

//code

DMX

Read and write from DMX512 devices. Must call SerCfg(250000, 513) before using these functions. The pins used for DMX are same as UART.

Function	Description
`DmxW([channels])`	Write `channel` byte array.
`DmxU()`	Enable receive to update internal buffer with incoming channels.
`DmxRdy()`	Returns 1 when there is a frame that was requested by `DmxU()`
`DmxR(channel)`	Returns the value of a specific channel.

tip

This feature only support DMX frames with Start Code zero.

Hosted-Language Samples

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Arduino

Start by setting up for Python or MicroPython.

#There is no library called DMX

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//code

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//code

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//code

Infrared

Receive and decode signals from Infrared remotes.

Function	Description
`IrEn(pin,enable)`	`enable` IR scanner on `pin`.
`IrRead()`	Returns key press value.

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Arduino

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duelink.Infrared.Read()

duelink.Infrared.Enable(pin: int, enable: bool)

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//code

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//code

Start by setting up for Arduino or C++.

//code

Temperature

Read temperature from a specific sensor

Function	Description
`Temp(pin, type)`	Read temperature sensor with `type` connected to `pin`. Returns temperature in Celsius.

ID	Type
0	Internal CPU temperature (pin is ignored)
1	DHT11
2	DHT12
3	DHT21
4	DHT22
5	One wire DS18B20 sensors

Hosted-Language Samples

Python
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Arduino

Start by setting up for Python or MicroPython.

duelink.Temperature.Read(pin: int, sensortype: int)

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//code

Start by setting up for .NET.

//code

Start by setting up for Arduino or C++.

//code

Humidity

Read humidity from a specific sensor.

Function	Description
`Humid(pin, type)`	Read a humidity sensor `type` connected to `pin`.

ID	Type
0	reserved
1	DHT11
2	DHT12
3	DHT21
4	DHT22

Hosted-Language Samples

Python
JavaScript
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Arduino

Start by setting up for Python or MicroPython.

duelink.Humidity.Read(pin: int, sensortype: int)

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//code

Start by setting up for .NET.

//code

Start by setting up for Arduino or C++.

//code

System Info

Read info about the system.

Function	Description
`Info(type)`	Returns the a specific `type` of info!

Type ID	Returned value
0	Product type
1	Firmware version

Hosted-Language Samples

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Arduino

Start by setting up for Python or MicroPython.

duelink.System.Info()

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//code

Start by setting up for .NET.

//code

Start by setting up for Arduino or C++.

//code

Graphics

DUELink firmware include a flexible graphics facilities, detailed on the Graphics Engine page.

File System

DUELink firmware include a complete file system facilities, detailed on the File System page.

Scheduler

See Scheduler for details.

Function	Description
`SStart("func", timeout, count)`	Schedule `func` to run at every `timeout` (in milliseconds) for `count` times, or -1 to run forever.
`Sstatled("func")`	`func`: Return how many times the schedule will still need to run for, 0 is complete and -1 ids forever.
`SAbort("func")`	`func`: Abort `func` scheduler.

Hosted-Language Samples

This is a script-only functionality!

Interrupts

See Interrupts for details.

Function	Description
`IStart("func", pin, trigger, pull)`	Enable interrupt on `pin` to trigger `func`. `trigger` is: 0 - falling, 1 - rising, 2 - rising and falling. Enable `pull`: 0 - pull down, 1 - pull up, 2 - no pull.
`Istatled("func")`	Return status of interrupt on `func`: 0- no interrupt, 1- active interrupt.
`IAbort("func")`	Abort interrupt for `func`.

Hosted-Language Samples

This is a script-only functionality.

Device Addressing

These functions are needed for helping with Daisylink devices chained through Downstream connections.

Function	Description
`Sel(add, add, add ...)`	Select a devices at `add` in the chain.
`GetAdd()`	Return the selected device(s) address.
`SetAdd(add)`	`add` Set the device's address. This command has chain reaction where each device sets the next one. This is a special command and should not be used.

The Sel(add) command accepts multiple addresses. Sel(3,7) will activate the third and and seventh modules in Daisylink. Any command issue from that point forward are executed by both modules. Zero is broadcast address, where Sel(0) will activate all modules. Use GetAdd() to detect what modules are currently active.

Hosted-Language Samples

Python
JavaScript
.NET
Arduino

Start by setting up for Python or MicroPython.

#No Library

Start by setting up for JavaScript.

//code

Start by setting up for .NET.

//code

Start by setting up for Arduino or C++.

//code

Math

Function	Description
`Rnd(max)`	Return a random number with `max` value.
`Cos(rad)`	Return cosine of `rad`.
`Sin(rad)`	Return sine of `rad`.
`Tan(rad)`	Return tangent `rad`.
`Sqrt(number)`	Return square root of `number`.
`Trunc(number)`	Return a truncated value `number`.
`IsNaN(number)`	Return 1 `number` is a valid value.

Details

Hosted-Language Samples

These are script-only functions.

Converters

Function	Description
`Str(number)`	Return a number as string (Good with `Text()`).
`Fmt(...)`	Return formatted string, works just like `Print()`.
`Scale(value, fromLow, fromHigh, toLow, toHigh)`	Return a scaled number from `value`.
`Memcpy([dst], offset_dst, [src], offset_src, count)`	Used to copy a block of memory from one location to another. `[dst]` and `[src]` must be same array type.

Details

Hosted-Language Samples

This is a script-only functionality.

Asynchronous IO

Enable Asynchronous IO. Detailed on the Engine main page.

Function	Description
`AsIo(enable)`	`enable`: 1 = Enable, 0 = Disable

Details

Hosted-Language Samples

This is a script-only functionality.

System Reset

Reset or clear the system.

Function	Description
`Reset(mode)`	Reset the system with `mode`.

mode	Description
0	System Reset (just like pressing reset button).
1	out the entire chip (factory reset!). This command must be executed twice for it to take effect.

Hosted-Language Samples

Python
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Arduino

Start by setting up for Python or MicroPython.

#Also appears in the System Info section
duelink.System.Reset()

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//code

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//code

Start by setting up for Arduino or C++.

//code

Low Power

Function	Description
`shtdn(wkpin)`	Shutdown module. `wkpin` can be pin P1 or P3.

Details

Hosted-Language Samples

This is a script-only functionality.

One-Time Programmable

Write and read from a special memory type that can be written only once and can never be erased or changed! The size of this special memory region is 512 bytes (64 8-Byte blocks).

Function	Description
`OtpR(addr)`	Read a single byte from `addr`.
`OtpW(addr, [data])`	*STOP Irreversible Action! Write `data` bytes to `addr`, where `addr` must be and data size must be multiple of 8. Return 1 on success, 0 if failed because an 8 byte block was previously written to.

tip

Use byte arrays. If float array is used then only the first byte of each element is written.

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Arduino

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#No Library

Start by setting up for JavaScript.

//code

Start by setting up for .NET.

//code

Start by setting up for Arduino or C++.

//code

Coprocessor

A few modules, such as USB Host include a coprocessor. See Coprocessor for more details.

RTC

Access clock and date in the internal Real Time Clock (RTC).

Function	Description
RtcW([timedate])	Set (write) the desired time and date from `timedate` array in the RTC.
RtcR([timedate])	Read the current time and date into array. If 0 is used instead of array then the rtc value is printed as `HH:MM:SS - DD MMM YYYY`.

The array used for all RTC functions is 6 bytes, organized as: [Second,minute,hour,day,mon, year]. Values must be proper for their field. For example, there is no 70 seconds in time. Also, year is starting from the year 2000. For year 2025, just use 25. Hours are military 24 hours.

Dim b1[6]= [0,10,18,27,2,25]
RtcW(b1) # Set the current time to 18:10:00 27 Feb 2025

Dim b2[6]
RtcR(b2) # Read the time into array
RtC(0) # Show the current time

tip

Power loss will cause the RTC to lose its value. This is where RTC comes in handy.

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Arduino

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#No Library

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//code

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//code

Start by setting up for Arduino or C++.

//code

Misc

Function	Description
`Version()`	Return firmware version and device ID in this format: `GHI Electronics DUELink v01.03:BB01`.
`Echo(enable)`	Set local echo functionality to `enable`: 1 = Enable or 0 = Disable. This is disabled by default. Run `Echo(1)` when using a terminal software.
`Len([array])`	Return the length of `array`.
`ReadVCC()`	Return current system voltage.
`Exit()`	Terminate and exit the script.

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Arduino

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#No Library
# Some are needed like System.ReadVCC() but others do nto make sense for hosted libs

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//code

Start by setting up for .NET.

//code

Start by setting up for Arduino or C++.

//code

Special Pins​

Print​

Timing​

Pin Control​

Stat LED​

Digital​

Analog​

Beep​

Melody​

Button​

Frequency​

Touch​

Digital Control​

Distance​

Servo Motors​

I2C​

SPI​

Serial (UART)​

DMX​

Infrared​

Temperature​

Humidity​

System Info​

Graphics​

File System​

Scheduler​

Interrupts​

Device Addressing​

Math​

Converters​

Asynchronous IO​

System Reset​

Low Power​

One-Time Programmable​

Coprocessor​

RTC​

Misc​

Special Pins

Print

Timing

Pin Control

Stat LED

Digital

Analog

Beep

Melody

Button

Frequency

Touch

Digital Control

Distance

Servo Motors

I2C

SPI

Serial (UART)

DMX

Infrared

Temperature

Humidity

System Info

Graphics

File System

Scheduler

Interrupts

Device Addressing

Math

Converters

Asynchronous IO

System Reset

Low Power

One-Time Programmable

Coprocessor

RTC

Misc