How to DHCP on Wiz830MJ?

Question

The project needs to do a DHCP request to get its IP address. However, the 5300 does an ARP request which naturally fails and does not send the DHCP request. How can the UDP send be forced or other solution to this problem?

jim · Answer

I need more info to investigate your problem in detail. I think you need to check bus interface between W5300 and host. Please refer to bus interface of W5300 Data sheet. (page 118 ~) The following link is WIZ830MJ EVB site. wiznet.io W5300E01-ARM | WIZnet Co., Ltd. Samsung ARM(S3C2410) based evaluation board for W5300 chip Thanks.

snorkack67 · Answer

Hi Jim, There is nothing wrong with the bus interface. I can read and write to the 5300 fine. The problem is that the 5300 wants to do an ARP request before sending out the DHCP discover message. At this point the 5300 knows only its Ethernet address. An ARP request can not get any useful information for the 5300. The DHCP server is the only host that can provide useful info to the 5300 and it will not answer an ARP request. It only answers a DHCP discover request. The ARP request fails and the 5300 gives up and won’t send the discover message. It appears that I need to use the mac raw mode to send out the discover message and when the DHCP server answers the 5300 will have an IP address and I can start using the 5300 UDP mode.