File content as of revision 0:1ed23ab1345f:

#if 1
/*
 * spp_demo
 */
#include "mbed.h"
#include <btstack/hci_cmds.h>
#include <btstack/run_loop.h>
#include <btstack/sdp_util.h>
#include "hci.h"
#include "l2cap.h"
#include "btstack_memory.h"
#include "remote_device_db.h"
#include "rfcomm.h"
#include "sdp.h"
#include "config.h"
#include "debug.h"
#include "bd_addr.h"  // class bd_addr

Serial pc(USBTX, USBRX);
DigitalOut led1(LED1), led2(LED2), led3(LED3);

#define HEARTBEAT_PERIOD_MS 500

static uint8_t   rfcomm_channel_nr = 1;
static uint16_t  rfcomm_channel_id = 0;
static uint8_t   spp_service_buffer[128];

// Bluetooth logic
static void packet_handler (void * connection, uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
    bd_addr_t event_addr;
    uint8_t   rfcomm_channel_nr;
    uint16_t  mtu;
    int err;
    switch (packet_type) {
        case HCI_EVENT_PACKET:
            switch (packet[0]) {
                    
                case BTSTACK_EVENT_STATE:
                    // bt stack activated, get started - set local name
                    if (packet[2] == HCI_STATE_WORKING) {
                        hci_send_cmd(&hci_write_local_name, "mbed");
                    }
                    break;
                
                case HCI_EVENT_COMMAND_COMPLETE:
                    if (COMMAND_COMPLETE_EVENT(packet, hci_read_bd_addr)){
                        bt_flip_addr(event_addr, &packet[6]);
                        log_info("BD-ADDR: %s\n\r", bd_addr_to_str(event_addr));
                        break;
                    }
                    if (COMMAND_COMPLETE_EVENT(packet, hci_write_local_name)){
                        hci_discoverable_control(1);
                        break;
                    }
                    break;

                case HCI_EVENT_LINK_KEY_REQUEST:
                    // deny link key request
                    log_info("Link key request\n\r");
                    bt_flip_addr(event_addr, &packet[2]);
                    hci_send_cmd(&hci_link_key_request_negative_reply, &event_addr);
                    break;
                    
                case HCI_EVENT_PIN_CODE_REQUEST:
                    // inform about pin code request
                    log_info("Pin code request - using '0000'\n\r");
                    bt_flip_addr(event_addr, &packet[2]);
                    hci_send_cmd(&hci_pin_code_request_reply, &event_addr, 4, "0000");
                    break;
                
                case RFCOMM_EVENT_INCOMING_CONNECTION:
                    // data: event (8), len(8), address(48), channel (8), rfcomm_cid (16)
                    bt_flip_addr(event_addr, &packet[2]); 
                    rfcomm_channel_nr = packet[8];
                    rfcomm_channel_id = READ_BT_16(packet, 9);
                    log_info("RFCOMM channel %u requested for %s\n\r", rfcomm_channel_nr, bd_addr_to_str(event_addr));
                    rfcomm_accept_connection_internal(rfcomm_channel_id);
                    break;
                    
                case RFCOMM_EVENT_OPEN_CHANNEL_COMPLETE:
                    // data: event(8), len(8), status (8), address (48), server channel(8), rfcomm_cid(16), max frame size(16)
                    if (packet[2]) {
                        log_info("RFCOMM channel open failed, status %u\n\r", packet[2]);
                    } else {
                        rfcomm_channel_id = READ_BT_16(packet, 12);
                        mtu = READ_BT_16(packet, 14);
                        log_info("\n\rRFCOMM channel open succeeded. New RFCOMM Channel ID %u, max frame size %u\n\r", rfcomm_channel_id, mtu);
                    }
                    break;
                    
                case RFCOMM_EVENT_CHANNEL_CLOSED:
                    rfcomm_channel_id = 0;
                    break;
                
                default:
                    break;
            }
            break;
            
        case RFCOMM_DATA_PACKET:
            // loopback
            if (rfcomm_channel_id) {
                err = rfcomm_send_internal(rfcomm_channel_id, packet, size);
                if (err) {
                    log_info("rfcomm_send_internal -> error %d", err);
                }
            }
            led3 = !led3;
            break;
        default:
            break;
    }
}

static void  heartbeat_handler(struct timer *ts){
    run_loop_set_timer(ts, HEARTBEAT_PERIOD_MS);
    run_loop_add_timer(ts);
    led2 = !led2;
} 

// main
int main(void)
{
    pc.baud(921600);
    log_info("%s\n", __FILE__);

    // init LEDs
    led1 = led2 = led3 = 1;
    
    /// GET STARTED with BTstack ///
    btstack_memory_init();
    run_loop_init(RUN_LOOP_EMBEDDED);
    
    // init HCI
    hci_transport_t* transport = hci_transport_usb_instance();
    remote_device_db_t * remote_db = (remote_device_db_t *) &remote_device_db_memory;
    hci_init(transport, NULL, NULL, remote_db);
    
    // init L2CAP
    l2cap_init();
    l2cap_register_packet_handler(packet_handler);
    
    // init RFCOMM
    rfcomm_init();
    rfcomm_register_packet_handler(packet_handler);
    rfcomm_register_service_internal(NULL, rfcomm_channel_nr, 100);  // reserved channel, mtu=100

    // init SDP, create record for SPP and register with SDP
    sdp_init();
    memset(spp_service_buffer, 0, sizeof(spp_service_buffer));
    service_record_item_t * service_record_item = (service_record_item_t *) spp_service_buffer;
    sdp_create_spp_service( (uint8_t*) &service_record_item->service_record, 1, "loopback");
    log_info("SDP service buffer size: %u\n\r", (uint16_t) (sizeof(service_record_item_t) + de_get_len((uint8_t*) &service_record_item->service_record)));
    sdp_register_service_internal(NULL, service_record_item);
    
    // set one-shot timer
    timer_source_t heartbeat;
    heartbeat.process = &heartbeat_handler;
    run_loop_set_timer(&heartbeat, HEARTBEAT_PERIOD_MS);
    run_loop_add_timer(&heartbeat);
    
    log_info("SPP loopback demo...\n\r");

     // turn on!
    hci_power_control(HCI_POWER_ON);

    // go!
    run_loop_execute();    

    return 0;
}
#endif