Search found 5 matches

by valery
Thu Nov 12, 2020 9:23 am
Forum: ESP-IDF
Topic: Obtain sender's MAC address for a UDP packet
Replies: 3
Views: 4282

Re: Obtain sender's MAC address for a UDP packet

ESP_Sprite wrote:
Thu Nov 12, 2020 1:16 am
Valery: The IP you're receiving from is associated with the MAC through arp. You might be able to use the LWIP call etharp_find_addr() or etharp_get_entry() to convert the IP back to the MAC.
Thank You :)
by valery
Wed Nov 11, 2020 10:16 am
Forum: ESP-IDF
Topic: Obtain sender's MAC address for a UDP packet
Replies: 3
Views: 4282

Obtain sender's MAC address for a UDP packet

When I receive a UDP packet from a remote computer, I need to determine the MAC address of the (remote) interface card from which it was sent. Is there any way to do this?
by valery
Wed May 13, 2020 5:42 pm
Forum: ESP-IDF
Topic: Where is math.h?
Replies: 4
Views: 8717

Re: Where is math.h?

Thank you. Is there a way to find location of a header file without IDE? Some time just want to look inside a header file, and wondering if IDF has some analog to 'whereis' tool.
by valery
Wed May 13, 2020 5:12 pm
Forum: Hardware
Topic: Large time gaps between I2C packets
Replies: 2
Views: 3265

Large time gaps between I2C packets

I'm tryig to send I2C read and write commands in rapid sequence as fast as it possible to a slave device. I2C clock speed is 400KHz. The picture below shows the I2C clock and data lines. As you can see, there are ~100uS gaps between write and read messages. That gap size is ~26,000 CPU clocks. It's ...
by valery
Sun May 03, 2020 12:25 pm
Forum: ESP-IDF
Topic: Where is math.h?
Replies: 4
Views: 8717

Where is math.h?

Hi, I try to use sqrt() and atan() functions. Where they are in IDF library? Which header file declares them?