About new ESP-NOW functions on SDK 1.2.0

[Ivan]

Hi,

Could you please kindly provide an example on how to use the new ESP-NOW functions on SDK 1.2.0?
I think I really need this for my project but just no idea on how to use it.
Thanks!

[parmar7725274]

Hi Ivan,

I'm also interested. Let me know if you get something.

Thanks & Regards,
Prakash P.

[kolban]

I'm not sure what this capability is supposed to do? Would anyone be able to post the intent of the new function?

Neil

[ESP_Faye]

Hi,

Here is a simple example

Code: Select all

void ICACHE_FLASH_ATTR simple_cb(u8 *macaddr, u8 *data, u8 len)
{
   int i;
   u8 ack_buf[16];
   u8 recv_buf[17];
   os_printf("now from[");
   for (i = 0; i < 6; i++)
      os_printf("%02X, ", macaddr[i]);
   os_printf(" len: %d]:", len);
   os_bzero(recv_buf, 17);
   os_memcpy(recv_buf, data, len<17?len:16);
   show_buf2(data,len);
   if (os_strncmp(data, "ACK", 3) == 0)
     return;

   os_sprintf(ack_buf, "ACK[%08x]", ack_count++);
   esp_now_send(macaddr, ack_buf, os_strlen(ack_buf));
 }
void user_init(void)
{
   u8 key[16]= {0x33, 0x44, 0x33, 0x44, 0x33, 0x44, 0x33, 0x44, 0x33, 0x44, 0x33, 0x44, 0x33, 0x44, 0x33, 0x44};
   u8 da1[6] = {0x18, 0xfe, 0x34, 0x97, 0xd5, 0xb1};
   u8 da2[6] = {0x1a, 0xfe, 0x34, 0x97, 0xd5, 0xb1};
   if (esp_now_init()==0) {
      os_printf("esp_now init ok\n");
      esp_now_register_recv_cb(simple_cb);
      os_printf("dlink send to A cur chan %d\n", wifi_get_channel());

      esp_now_set_self_role(1);
      esp_now_add_peer(da1, 1, key, 16);
      esp_now_add_peer(da2, 2, key, 16)
   } else {
     os_printf("esp_now init failed\n");
     }
 }
void ICACHE_FLASH_ATTR demo_send_(u8 *data, u8 len)
{
  /* the demo will send to two devices which added by esp_now_add_peer() */
    esp_now_send(NULL, data, len);

}


[Ivan]

Hi Faye,

Thanks for your response.
When I look at the example. It seems that the destination device must be an ESP8266 wifi module. Is that true?
Can I use ESP_NOW to send something to someone which is not an ESP device? like PC or mobile phone?

[ESP_Faye]

Hi,

Sorry that ESP-NOW only support ESP8266 device..

Thanks for your interest in ESP8266 !

[Ivan]

Hi Faye,

Ok, got it. Thanks!
I have another question.
Can I use a broadcast mac like: u8 da1[6] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
as destination so I can discover an unknown ESP8266 device then add it as my peer(slave)?

[ESP_Faye]

Hi,

Sorry that ESP-NOW can not broadcast right now..

But we will think over your request, and let you know if there is any update.

Thanks for your interest in Espressif Systems and ESP8266 !

[nice72]

Hi, All

I have two questions.

1. What is the difference between this controller mode and slave mode?

2. And, When the channel of the own and peer are not the same, esp8266 can send a packet to the peer esp8266?

3. I would like to know the meaning of the return value is 0 esp_now_is_peer_exist.
When we received the return 0, that esp8266 is going to disappear?

Thanks,

Peter.

[baoshi]

Hi Faye,

I tried the code you provided.

It seems I always get -4 error from esp_now_add_peer call. It there any clue what I did wrongly? (esp_now_init and esp_now_set_self_role is ok).

Also, would you please give a little explanation what is CONTROLLER role and what is SLAVE role?

Thanks

Baoshi