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Macros
#define	SNTP_SET_SYSTEM_TIME(sec)   LWIP_UNUSED_ARG(sec)
#define	SNTP_MAX_SERVERS   LWIP_DHCP_MAX_NTP_SERVERS
#define	SNTP_GET_SERVERS_FROM_DHCP   LWIP_DHCP_GET_NTP_SRV
#define	SNTP_SERVER_DNS   0
#define	SNTP_DEBUG   LWIP_DBG_OFF
#define	SNTP_PORT   123
#define	SNTP_CHECK_RESPONSE   0
#define	SNTP_STARTUP_DELAY   0
#define	SNTP_STARTUP_DELAY_FUNC   SNTP_STARTUP_DELAY
#define	SNTP_RECV_TIMEOUT   3000
#define	SNTP_UPDATE_DELAY   3600000
#define	SNTP_GET_SYSTEM_TIME(sec, us)   do { (sec) = 0; (us) = 0; } while(0)
#define	SNTP_RETRY_TIMEOUT   SNTP_RECV_TIMEOUT
#define	SNTP_RETRY_TIMEOUT_MAX   (SNTP_RETRY_TIMEOUT * 10)
#define	SNTP_RETRY_TIMEOUT_EXP   1

Detailed Description

Macro Definition Documentation

SNTP_SET_SYSTEM_TIME

#define SNTP_SET_SYSTEM_TIME

(

sec

)

LWIP_UNUSED_ARG(sec)

SNTP macro to change system time in seconds Define SNTP_SET_SYSTEM_TIME_US(sec, us) to set the time in microseconds instead of this one if you need the additional precision.

SNTP_MAX_SERVERS

#define SNTP_MAX_SERVERS   LWIP_DHCP_MAX_NTP_SERVERS

The maximum number of SNTP servers that can be set

SNTP_GET_SERVERS_FROM_DHCP

#define SNTP_GET_SERVERS_FROM_DHCP   LWIP_DHCP_GET_NTP_SRV

Set this to 1 to implement the callback function called by dhcp when NTP servers are received.

SNTP_SERVER_DNS

#define SNTP_SERVER_DNS   0

Set this to 1 to support DNS names (or IP address strings) to set sntp servers One server address/name can be defined as default if SNTP_SERVER_DNS == 1: #define SNTP_SERVER_ADDRESS "pool.ntp.org"

SNTP_DEBUG

#define SNTP_DEBUG   LWIP_DBG_OFF

SNTP_DEBUG: Enable debugging for SNTP.

SNTP_PORT

#define SNTP_PORT   123

SNTP server port

SNTP_CHECK_RESPONSE

#define SNTP_CHECK_RESPONSE   0

Set this to 1 to allow config of SNTP server(s) by DNS name Sanity check: Define this to

• 0 to turn off sanity checks (default; smaller code)
• >= 1 to check address and port of the response packet to ensure the response comes from the server we sent the request to.
• >= 2 to check returned Originate Timestamp against Transmit Timestamp sent to the server (to ensure response to older request).
• >= 3

SNTP_STARTUP_DELAY

#define SNTP_STARTUP_DELAY   0

According to the RFC, this shall be a random delay between 1 and 5 minutes (in milliseconds) to prevent load peaks. This can be defined to a random generation function, which must return the delay in milliseconds as u32_t. Turned off by default.

SNTP_STARTUP_DELAY_FUNC

#define SNTP_STARTUP_DELAY_FUNC   SNTP_STARTUP_DELAY

If you want the startup delay to be a function, define this to a function (including the brackets) and define SNTP_STARTUP_DELAY to 1.

SNTP_RECV_TIMEOUT

#define SNTP_RECV_TIMEOUT   3000

SNTP receive timeout - in milliseconds Also used as retry timeout - this shouldn't be too low. Default is 3 seconds.

SNTP_UPDATE_DELAY

#define SNTP_UPDATE_DELAY   3600000

SNTP update delay - in milliseconds Default is 1 hour. Must not be beolw 15 seconds by specification (i.e. 15000)

SNTP_GET_SYSTEM_TIME

#define SNTP_GET_SYSTEM_TIME	(		sec,
			us
	)		do { (sec) = 0; (us) = 0; } while(0)

SNTP macro to get system time, used with SNTP_CHECK_RESPONSE >= 2 to send in request and compare in response.

SNTP_RETRY_TIMEOUT

#define SNTP_RETRY_TIMEOUT   SNTP_RECV_TIMEOUT

Default retry timeout (in milliseconds) if the response received is invalid. This is doubled with each retry until SNTP_RETRY_TIMEOUT_MAX is reached.

SNTP_RETRY_TIMEOUT_MAX

#define SNTP_RETRY_TIMEOUT_MAX   (SNTP_RETRY_TIMEOUT * 10)

Maximum retry timeout (in milliseconds).

SNTP_RETRY_TIMEOUT_EXP

#define SNTP_RETRY_TIMEOUT_EXP   1

Increase retry timeout with every retry sent Default is on to conform to RFC.