diff options
| author | fishsoupisgood <github@madingley.org> | 2019-04-29 01:17:54 +0100 |
|---|---|---|
| committer | fishsoupisgood <github@madingley.org> | 2019-05-27 03:43:43 +0100 |
| commit | 3f2546b2ef55b661fd8dd69682b38992225e86f6 (patch) | |
| tree | 65ca85f13617aee1dce474596800950f266a456c /roms/u-boot/doc/README.SNTP | |
| download | qemu-master.tar.gz qemu-master.tar.bz2 qemu-master.zip | |
Diffstat (limited to 'roms/u-boot/doc/README.SNTP')
| -rw-r--r-- | roms/u-boot/doc/README.SNTP | 17 |
1 files changed, 17 insertions, 0 deletions
diff --git a/roms/u-boot/doc/README.SNTP b/roms/u-boot/doc/README.SNTP new file mode 100644 index 00000000..da9ec459 --- /dev/null +++ b/roms/u-boot/doc/README.SNTP @@ -0,0 +1,17 @@ +To use SNTP support, add define CONFIG_CMD_SNTP to the +configuration file of the board. + +The "sntp" command gets network time from NTP time server and +syncronize RTC of the board. This command needs the command line +parameter of server's IP address or environment variable +"ntpserverip". The network time is sent as UTC. So if you want to +set local time to RTC, set the offset in second from UTC to the +environment variable "time offset". + +If the DHCP server provides time server's IP or time offset, you +don't need to set the above environment variables yourself. + +Current limitations of SNTP support: +1. The roundtrip time is ignored. +2. Only the 1st NTP server IP, in the option ntp-servers of DHCP, will + be used. |