Send string in a Mesh. With nRF52DK

Question

Hello: 
 
 I have to nRF52DK boards and I am able to run the ligth_switch example, but the thing that I want to do is send a message, "hello" from one node to other. I saw the example in the Q&A, here but the example talks about the Mesh SDK v1.0.0. and I have the nrf5SDKforMeshv310src examples. 
 
 In the code I can't figure how to send a string. 
 Could you give me some clues to do it? 
 Thank you.

JEFT · Answer

Hello Sir viper1983 I got the messages to be sent and received over the light_switch example by modifying the type of every data variable to uint8_t * (you can notice that every data variables have the same bool type). 
 After that, I force the message to be unsegmented, that means that the message will only support like 9 characters, so, it's good to be aware about that. 
 then, I used a new opcode for receiving and sending string data over there. 
 These are the functions to be changed over the Generic OnOff client code on the generic_onoff_client.c 
 
static uint8_t message_set_packet_create(generic_onoff_set_msg_pkt_t *p_set, const generic_onoff_set_params_t * p_params,
 const model_transition_t * p_transition)
{
 p_set->on_off= p_params->on_off;
 p_set->tid = p_params->tid;

 if (p_transition != NULL)
 {
 p_set->transition_time = model_transition_time_encode(p_transition->transition_time_ms);
 p_set->delay = model_delay_encode(p_transition->delay_ms);
 return GENERIC_ONOFF_SET_MAXLEN; //I put a value of 9 over there
 }
 else
 {
 return GENERIC_ONOFF_SET_MINLEN;
 }
}

uint32_t generic_onoff_client_set(generic_onoff_client_t * p_client, const generic_onoff_set_params_t * p_params,
 const model_transition_t * p_transition)
{
 __LOG(LOG_SRC_APP, LOG_LEVEL_INFO, "%x
", p_client->model_handle);

 if (p_client == NULL || p_params == NULL)
 {
 return NRF_ERROR_NULL;
 }
 if (p_transition != NULL &&
 (p_transition->transition_time_ms > TRANSITION_TIME_MAX_MS ||
 p_transition->delay_ms > DELAY_TIME_MAX_MS))
 {
 return NRF_ERROR_INVALID_PARAM;
 }

 if (access_reliable_model_is_free(p_client->model_handle))
 {
 uint8_t server_msg_length = message_set_packet_create(&p_client->msg_pkt.set, p_params, p_transition);
 __LOG(LOG_SRC_APP, LOG_LEVEL_INFO, "p_params.onoff: %s
", p_client->msg_pkt.set.on_off);
 message_create(p_client, GENERIC_ONOFF_OPCODE_SET, p_client->msg_pkt.set.on_off,
 server_msg_length, &p_client->access_message.message);
 reliable_context_create(p_client, GENERIC_ONOFF_OPCODE_STATUS, &p_client->access_message);
 return access_model_reliable_publish(&p_client->access_message);
 }
 else
 {
 return NRF_ERROR_BUSY;
 }
} 
 This code is part of the Generic OnOff Server's code and should be modified. //This one is the new function that I use with the operational code
static void handle_send_status(access_model_handle_t model_handle, const access_message_rx_t * p_rx_msg, void * p_args){
 __LOG(LOG_SRC_APP, LOG_LEVEL_INFO, "A/C state: %s
", p_rx_msg->p_data);
}

static const access_opcode_handler_t m_opcode_handlers[] =
{
 {ACCESS_OPCODE_SIG(GENERIC_ONOFF_OPCODE_SET), handle_set},
 {ACCESS_OPCODE_SIG(GENERIC_ONOFF_OPCODE_SET_UNACKNOWLEDGED), handle_set},
 {ACCESS_OPCODE_SIG(GENERIC_ONOFF_OPCODE_GET), handle_get},
 {ACCESS_OPCODE_SIG(OPCODE_SEND_STATUS), handle_send_status}, //I added this one
};