bt_gatt_client_write()

Description

Function writes data to a specific attribute via handle.

Syntax

bt_gatt_client_write(connection_id, handle, offset, lengh, data[]);

Parameters

Variable	Input

Variable	Input
`connection_id`	Connection id which was described in `bt_gatt_client_connect` function. Could be either 0 or 1.
`handle`	Handle of attribute to write data to. Handle limits are from 0x0001 to 0xFFFF.
`offset`	Data offset.
`length`	Data length to write.
`data[]`	Data array to write.

Returns

Return value	Return explanation
SCRIPT_OPERATION_SUCCESS	Write operation was successful.
SCRIPT_OPERATION_FAILED	Write operation failed.
SCRIPT_NO_ACCESS	Bluetooth GATT client is not initialized.
SCRIPT_PARAM_INVALID	Could be one of the following: Incorrect connection id Handle is out of bounds. Offset too high or too low. Write length is too high or too low. Passed data array is smaller than requested write length.

Function call example

#include <io>
#include <read>
#include <float>
#include <string>
#include <core>
#include <write>
#include <define>
#include <socket>
#include <bluetooth>

#define FIRST_CONNECTION       0
#define SECOND_CONNECTION      1

new peer_mac_address[MAC_ADDR_SIZE] = [0xFF, 0x48, 0x80, 0x33, 0xE3, 0xA8];
new handle_to_write_to = 0x0D;
new data_write_offset = 0;
new data_to_write[3] = [0x41, 0x42, 0x43];

main()
{   
    bt_init();
    bt_gatt_client_init();
    while (bt_gatt_client_connect(FIRST_CONNECTION, BT_ADDR_RANDOM, peer_mac_address) != SCRIPT_OPERATION_SUCCESS)
    {
        Delay(100);
    }
    bt_gatt_client_write(FIRST_CONNECTION, handle_to_write_to, data_write_offset, sizeof(data_to_write), data_to_write);
    for(;;)
    {
        Delay(100);
    }
}

Debug example

This example initializes BLE, then initializes GATT Client module, connects to peer device and writes some data to an attribute. Example uses debug_print function to print information log to Initialized peripheral.

#include <io>
#include <read>
#include <float>
#include <string>
#include <core>
#include <write>
#include <define>
#include <socket>
#include <bluetooth>
#include <debug>

#define RS232_SPEED         115200
#define WORD_LENGTH         WORDLENGTH_8
#define STOP_BITS           STOPBITS_1
#define PARITY              PARITY_NONE

#define FIRST_CONNECTION       0
#define SECOND_CONNECTION      1

new peer_mac_address[] = [0xFF, 0x48, 0x80, 0x33, 0xE3, 0xA8];
new handle_to_write_to = 0x0D;
new data_write_offset = 0;
new data_to_write[3] = [0x41, 0x42, 0x43];
new return_code = SCRIPT_OPERATION_SUCCESS;

main()
{
    Init(RS232, RS232_SPEED, WORD_LENGTH, STOP_BITS, PARITY);
    debug_init(RS232);
    return_code = bt_init();
    if (return_code != SCRIPT_OPERATION_SUCCESS)
    {
        // Handle failed bt_init here
        debug_print("bt_init failed\r\n");
    }
    else 
    {
        debug_print("bt_init succeeded\r\n");
    }
    return_code = bt_gatt_client_init();
    if (return_code != SCRIPT_OPERATION_SUCCESS)
    {
        // Handle failed bt_gatt_client_init here
        debug_print("bt_gatt_client_init failed\r\n");
    }
    else 
    {
        debug_print("bt_gatt_client_init succeeded\r\n");
    }
    debug_print("Connecting to a device with this MAC address: %X:%X:%X:%X:%X:%X\r\n", peer_mac_address[0], 
                peer_mac_address[1], peer_mac_address[2], peer_mac_address[3], peer_mac_address[4], peer_mac_address[5]);
    while (bt_gatt_client_connect(FIRST_CONNECTION, BT_ADDR_RANDOM, peer_mac_address) != SCRIPT_OPERATION_SUCCESS)
    {
        debug_print("bt_gatt_client_connect time-out\r\n");
        Delay(100);
    }
    debug_print("Connected successfully\r\n");
    return_code = bt_gatt_client_write(FIRST_CONNECTION, handle_to_write_to, data_write_offset, sizeof(data_to_write), data_to_write);
    if (return_code != SCRIPT_OPERATION_SUCCESS)
    {
        // Handle failed bt_gatt_client_write here
        debug_print("bt_gatt_client_write failed\r\n");
    }
    else 
    {
        debug_print("bt_gatt_client_write succeeded\r\n");
    }
    for(;;)
    {   
        Delay(1000);
    }
}