Wire

Read/write two-wire serial (I2C) master (mwx::periph_wire)

Reads and writes two-wire serial (I2C) master.

Alias Definition

using TwoWire = mwx::periph_twowire<MWX_TWOWIRE_RCVBUFF>;

The mwx::periph_wire<MWX_TWOWIRE_RCVBUFF> can be referred as TwoWire.

Type Definitions

The following definition types describe the types of arguments and return values.

typedef uint8_t size_type;
typedef uint8_t value_type;

hint style="warning %}

Some APIs make calls where the STOP bit is not strictly handled.

write(), writer::operator() () has several arguments defined in addition to the ones described here.

• fixed array type uint8_t cmds[]={11,12}; ... Wire.write(cmds);

• initializer_list<> 型 Wire.write({11,12})

Initialization and termination

Wire Instance Creation

Instance creation and necessary initialization is done in the library. In user code, it is made available by calling Wire.begin().

When using the requestFrom() method, you can specify the size of the FIFO queue for temporary data storage. At compile time, compile the macro MWX_TWOWIRE_BUFF with the required number of bytes. The default is 32 bytes.

Example: -DMWX_TWOWIRE_BUFF=16

begin()

void begin(
    const size_type u8mode = WIRE_100KHZ,
    bool b_portalt = false)

Initialize hardware.

Performing any Wire operation without initialization will cause the TWELITE radio module to hang.

When waking from sleep, if the module was operating just before sleep, it will return to the previous state.

Parameters	Description
u8mode	Specifies the bus frequency. Default is 100Khz (WIRE_CONF::WIRE_100KHZ) The frequency is specified by WIRE_CONF::WIRE_? KHZ and ? KHZ can be 50,66,80,100,133,160,200,266,320,400.
b_portalt	Change hardware pin assignments.

Example

void setup() {
    ...
    Wire.begin();
    ...
}

void wakeup() {
    ...
    Wire.begin();
    ...
}

Reading and Writing

There are two types of read/write procedures. Select and use one of them.

• Member function (input/output using the following member functions) requestFrom(), beginTransmission(), endTransmission(), write()

• Helper class (stream function available) reader, writer

Others

Probe（Determine presence of device)

bool probe(uint8_t address)

Checks if the device specified by address is responding. If the device exists, true is returned.

setClock()

void setClock(uint32_t speed)

The procedure is originally intended to change the bus frequency, but no action is taken.