W5100E01-AVR WIZnet, W5100E01-AVR Datasheet - Page 89

• Manufacturer Part Number: W5100E01-AVR
• Description: Development Boards & Kits - AVR W5100 EVAL BOARD BASED ON AVR
• Manufacturer: WIZnet

Specifications of W5100E01-AVR

• Rohs: yes
• Product: Development Boards
• Tool Is For Evaluation Of: ATMEGA128
• Core: AVR8
• Interface Type: LAN, RS-232
• Operating Supply Voltage: 5 V
• Data Bus Width: 8 bit

DNS Resolver works based on gethostbyaddr() and gethostbyname(). gethostbyaddr() transforms Internet IP
Address to Internet Domain Name and gethostbyname() transforms Internet Domain Name to Internet IP
Address. gethostbyaddr() and gethostbyname() test the setup of DNS Name Server IP Address and search
free channels of W5100 needed for connection with DNS Name Server. If a free channel of W5100 exists,
gethostbyaddr() and gethostbyname() call dns_query() with ‘BYNAME’ or ‘BYIP’ as the elements.
For examples of gethostbyaddr() and gethostbyname(), refer to
Actual connection with DNS Name Server is performed through dns_query(), and gethostbyaddr() and
gethostbyname() are reporting only the result of dns_query().
/* Header Section */
typedef struct _DHDR
{
}DHDR;
/* Question Section */
typedef struct _QUESTION
{
//
}DQST;
/* Resource Records */
typedef struct _RESOURCE_RECORD
{
//
//
}DRR;
typedef enum _QUERYDATA{BYNAME,BYIP}QUERYDATA;
u_int
u_char flag0;
u_char flag1;
u_int
u_int
u_int
u_int
char* qname;
u_int qtype;
u_int qclass;
char*
u_int
u_int
u_long
u_int
char*
© Copyright 2007 WIZnet Co., Inc. All rights reserved.
_rdlen;
_rdata;
_type;
<Table 3-38: Query Type Definition at dns_query()>
id;
qdcount; /* Question count */
ancount; /* Answer count */
nscount; /* Authority (name server) count */
arcount; /* Additional record count */
_name;
_class;
_ttl;
<Table 3-37: DNS Message Data Type>
/* Identification */
// Variable length data
// Variable length data
// Variable length data
Chapter 3.2.5.3
/* Query type */
Ping Request Program.
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