Hi Terje
Thanks for your interest in this issue. Below I describe a summary:
1. I use the example code "beacon" (...\ncs\v1.5.0\zephyr\samples\bluetooth\ibeacon) because I want to send the data from an analog sensor to the Connect app, and first at all I want to simulate the sending of data in integer format. Below I show you the "main.c" code and a screenshot without making changes:
#include <zephyr/types.h>
#include <stddef.h>
#include <sys/printk.h>
#include <sys/util.h>
#include <bluetooth/bluetooth.h>
#include <bluetooth/hci.h>
#define DEVICE_NAME CONFIG_BT_DEVICE_NAME
#define DEVICE_NAME_LEN (sizeof(DEVICE_NAME) - 1)
/*
* Set Advertisement data. Based on the Eddystone specification:
* https://github.com/google/eddystone/blob/master/protocol-specification.md
* https://github.com/google/eddystone/tree/master/eddystone-url
*/
static const struct bt_data ad[] = {
BT_DATA_BYTES(BT_DATA_FLAGS, BT_LE_AD_NO_BREDR),
BT_DATA_BYTES(BT_DATA_UUID16_ALL, 0xaa, 0xfe),
BT_DATA_BYTES(BT_DATA_SVC_DATA16,
0xaa, 0xfe, /* Eddystone UUID */
0x10, /* Eddystone-URL frame type */
0x00, /* Calibrated Tx power at 0m */
0x00, /* URL Scheme Prefix http://www. */
'z', 'e', 'p', 'h', 'y', 'r',
'p', 'r', 'o', 'j', 'e', 'c', 't',
0x08) /* .org */
};
/* Set Scan Response data */
static const struct bt_data sd[] = {
BT_DATA(BT_DATA_NAME_COMPLETE, DEVICE_NAME, DEVICE_NAME_LEN),
};
static void bt_ready(int err)
{
char addr_s[BT_ADDR_LE_STR_LEN];
bt_addr_le_t addr = {0};
size_t count = 1;
if (err) {
printk("Bluetooth init failed (err %d)\n", err);
return;
}
printk("Bluetooth initialized\n");
/* Start advertising */
err = bt_le_adv_start(BT_LE_ADV_NCONN_IDENTITY, ad, ARRAY_SIZE(ad),
sd, ARRAY_SIZE(sd));
if (err) {
printk("Advertising failed to start (err %d)\n", err);
return;
}
/* For connectable advertising you would use
* bt_le_oob_get_local(). For non-connectable non-identity
* advertising an non-resolvable private address is used;
* there is no API to retrieve that.
*/
bt_id_get(&addr, &count);
bt_addr_le_to_str(&addr, addr_s, sizeof(addr_s));
printk("Beacon started, advertising as %s\n", addr_s);
}
void main(void)
{
int err;
printk("Starting Beacon Demo\n");
/* Initialize the Bluetooth Subsystem */
err = bt_enable(bt_ready);
if (err) {
printk("Bluetooth init failed (err %d)\n", err);
}
}
2.- Now I make a small change to the code "main.c" to see the integer value: 999, and I see the 0xE7 in the app.
const int test_int = 999;
static const struct bt_data ad[] = {
BT_DATA_BYTES(BT_DATA_FLAGS, BT_LE_AD_NO_BREDR),
// BT_DATA_BYTES(BT_DATA_UUID16_ALL, 0xaa, 0xfe),
BT_DATA_BYTES(test_int),
BT_DATA_BYTES(BT_DATA_SVC_DATA16,
0xaa, 0xfe, /* Eddystone UUID */
0x10, /* Eddystone-URL frame type */
0x00, /* Calibrated Tx power at 0m */
0x00, /* URL Scheme Prefix http://www. */
'z', 'e', 'p', 'h', 'y', 'r',
'p', 'r', 'o', 'j', 'e', 'c', 't',
0x08) /* .org */
};
3.- Finally I make another small change to the code "main.c" to see the value char: 999, and again I see the 0xE7 in the app.
const char test_char = 999;
static const struct bt_data ad[] = {
BT_DATA_BYTES(BT_DATA_FLAGS, BT_LE_AD_NO_BREDR),
// BT_DATA_BYTES(BT_DATA_UUID16_ALL, 0xaa, 0xfe),
BT_DATA_BYTES(test_char),
BT_DATA_BYTES(BT_DATA_SVC_DATA16,
0xaa, 0xfe, /* Eddystone UUID */
0x10, /* Eddystone-URL frame type */
0x00, /* Calibrated Tx power at 0m */
0x00, /* URL Scheme Prefix http://www. */
'z', 'e', 'p', 'h', 'y', 'r',
'p', 'r', 'o', 'j', 'e', 'c', 't',
0x08) /* .org */
};
4.- Today I'm working with strings using "sprintf". The code below compiles fine, but I still don't know how to add the string "buffer" to the data of "static const struct bt_data ad []":
int test()
{
char buffer[50];
int a = 10, b = 20, c;
c = a + b;
sprintf(buffer, "Sum of %d and %d is %d", a, b, c);
// The string "sum of 10 and 20 is 30" is stored
// into buffer instead of printing on stdout
return 0;
}
I feel like I'm close to the solution, and I'm just trying ideas and none of them satisfy me ... Anything on your mind?
Regards
Guillermo
