Meadow.Foundation.ICs.IOExpanders.Tca9548a

Tca9548a
Status
Source code	GitHub
Datasheet(s)	GitHub
NuGet package

[Explanation of the peripheral]

Code Example

IDigitalOutputPort bus0Port0;
IDigitalOutputPort bus1Port0;

public override Task Initialize()
{
    Resolver.Log.Info("Initialize...");

    var i2cBus = Device.CreateI2cBus(I2cBusSpeed.Standard);
    var tca9548a = new Tca9548a(i2cBus, 0x70);
    var mcp0 = new Mcp23008(tca9548a.Bus0);
    var mcp1 = new Mcp23008(tca9548a.Bus1);

    bus0Port0 = mcp0.CreateDigitalOutputPort(mcp0.Pins.GP0);
    bus1Port0 = mcp1.CreateDigitalOutputPort(mcp1.Pins.GP0);

    return base.Initialize();
}

public override async Task Run()
{
    while (true)
    {
        bus0Port0.State = true;
        bus1Port0.State = false;

        await Task.Delay(1000);

        bus0Port0.State = false;
        bus1Port0.State = true;

        await Task.Delay(1000);
    }
}

Sample project(s) available on GitHub

Wiring Example

To wire a Tca9548a to your Meadow board, connect the following:

Tca9548a	Meadow Pin
GND	GND
SCL	D08 (SCL)
SDA	D07 (SDA)
VCC	3V3

It should look like the following diagram:

ToDo: Fritzing diagram here

Class Tca9548a

A TCA9548A i2c multiplexer

Assembly: Tca9548a.dll

View Source

Declaration

public class Tca9548a : II2cCommunications, IByteCommunications

Implements:
Meadow.Hardware.II2cCommunications, Meadow.Hardware.IByteCommunications

Properties

Address

The address of this device on the Meadow.Foundation.ICs.IOExpanders.Tca9548a.Bus

View Source

Declaration

public byte Address { get; }

Bus

The Meadow.Hardware.II2cBus this device is connected to.

View Source

Declaration

public II2cBus Bus { get; }

Bus0

The Meadow.Hardware.II2cBus connected to SD0/SC0

View Source

Declaration

public II2cBus Bus0 { get; }

Bus1

The Meadow.Hardware.II2cBus connected to SD1/SC1

View Source

Declaration

public II2cBus Bus1 { get; }

Bus2

The Meadow.Hardware.II2cBus connected to SD2/SC2

View Source

Declaration

public II2cBus Bus2 { get; }

Bus3

The Meadow.Hardware.II2cBus connected to SD3/SC3

View Source

Declaration

public II2cBus Bus3 { get; }

Bus4

The Meadow.Hardware.II2cBus connected to SD4/SC4

View Source

Declaration

public II2cBus Bus4 { get; }

Bus5

The Meadow.Hardware.II2cBus connected to SD5/SC5

View Source

Declaration

public II2cBus Bus5 { get; }

Bus6

The Meadow.Hardware.II2cBus connected to SD6/SC6

View Source

Declaration

public II2cBus Bus6 { get; }

Bus7

The Meadow.Hardware.II2cBus connected to SD7/SC7

View Source

Declaration

public II2cBus Bus7 { get; }

Methods

Write(Span<byte>)

Write an array of bytes to the peripheral

View Source

Declaration

public void Write(Span<byte> data)

Parameters

Type	Name	Description
System.Span<System.Byte>	data	Values to be written

WriteRegister(byte, uint, ByteOrder)

Write an unsigned integer to the peripheral

View Source

Declaration

public void WriteRegister(byte address, uint value, ByteOrder order = ByteOrder.LittleEndian)

Parameters

Type	Name	Description
System.Byte	address	Address to write the first byte to
System.UInt32	value	Value to be written
Meadow.ByteOrder	order	Indicate if the data should be written as big or little endian

WriteRegister(byte, ulong, ByteOrder)

Write an unsigned long to the peripheral.

View Source

Declaration

public void WriteRegister(byte address, ulong value, ByteOrder order = ByteOrder.LittleEndian)

Parameters

Type	Name	Description
System.Byte	address	Address to write the first byte to
System.UInt64	value	Value to be written
Meadow.ByteOrder	order	Indicate if the data should be written as big or little endian

Write(byte)

Write a single byte to the peripheral.

View Source

Declaration

public void Write(byte value)

Parameters

Type	Name	Description
System.Byte	value	Value to be written (8-bits)

WriteRegister(byte, ushort, ByteOrder)

Write an unsigned short to the peripheral.

View Source

Declaration

public void WriteRegister(byte address, ushort value, ByteOrder order = ByteOrder.LittleEndian)

Parameters

Type	Name	Description
System.Byte	address	Address to write the first byte to
System.UInt16	value	Value to be written (16-bits)
Meadow.ByteOrder	order	Indicate if the data should be written as big or little endian

WriteRegister(byte, byte)

Write data to a register in the peripheral

View Source

Declaration

public void WriteRegister(byte address, byte value)

Parameters

Type	Name	Description
System.Byte	address	Address of the register to write to
System.Byte	value	Data to write into the register

ReadBytes(ushort)

Read bytes from the I2cBus

View Source

Declaration

public byte[] ReadBytes(ushort numberOfBytes)

Returns

System.Byte[]

Parameters

Type	Name
System.UInt16	numberOfBytes

ReadRegister(byte)

Read a register from the peripheral

View Source

Declaration

public byte ReadRegister(byte address)

Returns

System.Byte

Parameters

Type	Name	Description
System.Byte	address	Address of the register to read.

ReadRegisterAsUShort(byte, ByteOrder)

Read an unsigned short from a register

View Source

Declaration

public ushort ReadRegisterAsUShort(byte address, ByteOrder order)

Returns

System.UInt16

Parameters

Type	Name	Description
System.Byte	address	Register address of the low byte (the high byte will follow).
Meadow.ByteOrder	order	Order of the bytes in the register (little endian is the default).

Read(Span<byte>)

Reads data from the peripheral

View Source

Declaration

public void Read(Span<byte> readBuffer)

Parameters

Type	Name
System.Span<System.Byte>	readBuffer

Exceptions

System.NotImplementedException

ReadRegister(byte, Span<byte>)

Reads data from the peripheral starting at the specified address

View Source

Declaration

public void ReadRegister(byte address, Span<byte> readBuffer)

Parameters

Type	Name
System.Byte	address
System.Span<System.Byte>	readBuffer

WriteRegister(byte, Span<byte>, ByteOrder)

Write data to a register in the peripheral

View Source

Declaration

public void WriteRegister(byte address, Span<byte> writeBuffer, ByteOrder order = ByteOrder.LittleEndian)

Parameters

Type	Name	Description
System.Byte	address	Address of the register to write to
System.Span<System.Byte>	writeBuffer	A buffer of byte values to be written
Meadow.ByteOrder	order	Indicate if the data should be written as big or little endian

Exchange(Span<byte>, Span<byte>, DuplexType)

Write data to followed by read data from the peripheral.

View Source

Declaration

public void Exchange(Span<byte> writeBuffer, Span<byte> readBuffer, DuplexType duplex)

Parameters

Type	Name	Description
System.Span<System.Byte>	writeBuffer	Data to write
System.Span<System.Byte>	readBuffer	Buffer where read data will be written. Number of bytes read is determined by buffer size.
Meadow.Hardware.DuplexType	duplex	Whether the communication will happen in a half-duplex or full-duplex fashion.

Implements

• Meadow.Hardware.II2cCommunications
• Meadow.Hardware.IByteCommunications