HMTRP Class Reference

API for the HM-TRP Serial RF Pro transceiver. More...

Detailed Description

• ID: hmtrp
• Name: Serial RF Pro Module
• Other Names: HMTRP-433 HMTRP-470 HMTRP-868 HMTRP-915
• Category: wifi
• Manufacturer: seeed
• Connection: uart
• Link: http://wiki.seeed.cc/Grove-Serial_RF_Pro/

UPM support for the HM-TRP Serial RF Pro transceiver. This was tested specifically with the Grove Serial RF Pro transceiver. In theory, this class should work with the following devices:

HM-TRP-433: 414000000-454000000Hz HM-TRP-470: 450000000-490000000Hz HM-TRP-868: 849000000-889000000Hz HM-TRP-915: 895000000-935000000Hz

The only difference is the transmit and receive frequencies supported.

By default, the device simply sends and receives any data presented on its UART interface. It can be put into a configuration mode by grounding the CONFIG pin on the transceiver.

    // Instantiate a HMTRP radio device on uart 0

    upm::HMTRP radio(0);

    // make sure port is initialized properly.  9600 baud is the default.
    if (!radio.setupTty(B9600)) {
        cerr << "Failed to setup tty port parameters" << endl;
        return 1;
    }

    printUsage();

    // By default, this radio simply transmits data sent via writeData()
    // and reads any available data via readData().

    // It can be placed into a configuration mode by grounding the
    // CONFIG pin on the module.  When this is done, the various
    // configuration query and config methods can be used.  In this
    // example, by default, we just read any data available fom the
    // device, and periodically transmit "Hello World".

    // If any argument was specified on the command line, do a simple
    // configuration query and output the results.  The radio must be in
    // CONFIG mode for this to work.

    if (argc > 1) {
        // config mode
        uint32_t freq;
        uint32_t dataRate;
        uint16_t rxBandwidth;
        uint8_t modulation;
        uint8_t txPower;
        uint32_t uartBaud;

        if (radio.getConfig(&freq, &dataRate, &rxBandwidth, &modulation, &txPower, &uartBaud)) {
            cout << "Radio configuration:" << endl;
            cout << "freq: " << freq << " dataRate: " << dataRate << " rxBandwidth: " << rxBandwidth
                 << "Khz" << endl;

            cout << "modulation: " << int(modulation) << "Khz txPower: " << int(txPower)
                 << " uartBaud: " << uartBaud << endl;
        } else {
            cerr << "getConfig() failed.  Make sure the radio is in "
                 << "CONFIG mode." << endl;
        }
    } else {
        // normal read/write mode
        char radioBuffer[bufferLength];
        int counter = 0;
        cout << "Running in normal read/write mode." << endl;

        while (shouldRun) {
            // we don't want the read to block in this example, so always
            // check to see if data is available first.
            if (radio.dataAvailable()) {
                memset(radioBuffer, 0, bufferLength);
                int rv = radio.readData(radioBuffer, bufferLength - 1);

                if (rv > 0)
                    cout << "Received: " << radioBuffer << endl;

                if (rv < 0) // some sort of read error occurred
                {
                    cerr << "Port read error." << endl;
                    break;
                }

                continue;
            }

            upm_delay_us(100000); // 100ms
            counter++;
            // every second, transmit "Hello World"
            if (counter > 10) {
                static const char* hello = "Hello World!";
                cout << "Transmitting hello world..." << endl;
                radio.writeData((char*) hello, strlen(hello) + 1);
                counter = 0;
            }
        }
    }

Public Types
enum	HMTRP_OPCODE_T {   RESET = 0xf0, GET_CONFIG = 0xe1, SET_FREQUENCY = 0xd2, SET_RF_DATARATE = 0xc3,   SET_RX_BW = 0xb4, SET_FREQ_MODULATION = 0xa5, SET_TX_POWER = 0x96, SET_UART_SPEED = 0x1e,   GET_RF_SIGNAL_STR = 0xa7, GET_MOD_SIGNAL_STR = 0x78 }

Public Member Functions
	HMTRP (int uart=HMTRP_DEFAULT_UART)
	~HMTRP ()
bool	dataAvailable (unsigned int millis=0)
int	readData (char *buffer, int len, int millis=-1)
int	writeData (char *buffer, int len)
bool	setupTty (speed_t baud=B9600)
bool	checkOK ()
bool	reset ()
bool	getConfig (uint32_t *freq, uint32_t *dataRate, uint16_t *rxBandwidth, uint8_t *modulation, uint8_t *txPower, uint32_t *uartBaud)
bool	setFrequency (uint32_t freq)
bool	setRFDataRate (uint32_t rate)
bool	setRXBandwidth (uint16_t rxBand)
bool	setFrequencyModulation (uint8_t modulation)
bool	setTransmitPower (uint8_t power)
bool	setUARTSpeed (uint32_t speed)
bool	getRFSignalStrength (uint8_t *strength)
uint8_t	getRFSignalStrength ()
bool	getModSignalStrength (uint8_t *strength)
uint8_t	getModSignalStrength ()

Constructor & Destructor Documentation

HMTRP

(

int

uart = HMTRP_DEFAULT_UART

)

HMTRP Serial RF Pro transceiver constructor

Parameters

uart	Default UART to use (0 or 1)

~HMTRP

(

)

HMTRP destructor

Member Function Documentation

bool dataAvailable

(

unsigned int

millis = 0

)

Checks to see if there is data available for reading

Parameters

millis

Number of milliseconds to wait; 0 means no waiting (default).

Returns

True if there is data available for reading

int readData	(	char *	buffer,
		int	len,
		int	millis = -1
	)

Reads any available data in a user-supplied buffer

Parameters

buffer	Buffer to hold the data read
len	Length of the buffer
millis	Maximum time in milliseconds to wait for input. -1 means waiting forever (default).

Returns

Number of bytes read; 0 if timed out and millis is >= 0

int writeData	(	char *	buffer,
		int	len
	)

Writes the data in the buffer to the device

Parameters

buffer	Buffer to hold the data read
len	Length of the buffer

Returns

Number of bytes written

bool setupTty

(

speed_t

baud = B9600

)

Sets up proper tty I/O modes and the baud rate. The default baud rate is 9,600 (B9600).

Parameters

baud	Desired baud rate.

Returns

True if successful

bool checkOK

(

)

Looks for and verifies an OK response. This looks like "OK\r\n"

Returns

True if OK received

bool reset

(

)

Resets the device to default parameters, except for the UART baud rate

Returns

True if successful

bool getConfig	(	uint32_t *	freq,
		uint32_t *	dataRate,
		uint16_t *	rxBandwidth,
		uint8_t *	modulation,
		uint8_t *	txPower,
		uint32_t *	uartBaud
	)

Queries the radio to determine its configuration

Parameters

freq	Operating frequency
dataRate	TX/RX bit rate
rxBandwidth	Receiving bandwidth in Khz
modulation	Modulation frequency in Khz
txPower	Transmission power (1-7)
uartBaud	UART baud rate

Returns

True if successful

bool setFrequency

(

uint32_t

freq

)

Sets the frequency. Note: this is limited depending on which HM-TRP device you are using. Consult the datasheet.

Parameters

freq	Operating frequency

Returns

True if successful

bool setRFDataRate

(

uint32_t

rate

)

Sets the RF data transmission rate. Valid values are between 1,200 and 115,200.

Parameters

rate	Radio transmission rate in baud (1,200-115,200)

Returns

True if successful

bool setRXBandwidth

(

uint16_t

rxBand

)

Sets the RX bandwidth. Valid values are between 30 and 620 (in Khz)

Parameters

rxBand

RX bandwidth in Khz (30-620)

Returns

True if successful

bool setFrequencyModulation

(

uint8_t

modulation

)

Sets the frequency modulation. Valid values are between 10 and 160 (in Khz)

Parameters

modulation

Frequency modulation to use, in Khz (10-160)

Returns

True if successful

bool setTransmitPower

(

uint8_t

power

)

Sets the transmit power level. Valid values are between 0 and 7, 7 being the maximum power.

Parameters

power

Power level to use during transmission. Valid values are between 0 and 7.

Returns

True if successful

bool setUARTSpeed

(

uint32_t

speed

)

Sets the configured baud rate of the UART. It is strongly recommended you do not change this, or you may lose the ability to communicate with the transceiver. Valid values are 1,200-115,200.

Parameters

speed

Desired baud rate to configure the device to use Valid values are between 1,200 and 115,200.

Returns

True if successful

bool getRFSignalStrength

(

uint8_t *

strength

)

Gets the RF signal strength

Parameters

strength

Returned strength

Returns

True if successful

uint8_t getRFSignalStrength

(

)

Gets the RF signal strength

Returns

Signal strength

Exceptions

std::runtime_error

if reading from the sensor failed

bool getModSignalStrength

(

uint8_t *

strength

)

Gets the modulation signal strength.

Parameters

strength

Returned strength

Returns

True if successful

uint8_t getModSignalStrength

(

)

Gets the modulation signal strength.

Returns

Signal strength

Exceptions

std::runtime_error

if reading from the sensor failed

---

The documentation for this class was generated from the following files:

• src/hmtrp/hmtrp.hpp
• src/hmtrp/hmtrp.cxx