SmartGPU2-LCD480X320Touch-CommandSet

SMART GPU 2 3.5” TOUCH
Command Set
Vizic Technologies ©2014 120
2.10.1 RTC Setup –53hex – ‘S’ ascii
Commands (host)
2 bytes
1.- 0x52 (hex), R (ascii). *RTC command.
2.- 0x53 (hex), S (ascii).
Responses (device)
2 bytes
1.- RTC State: 0x00 Stopped or
0x01 Configured and Running.
2.- 0x4F (hex), O (ascii) – success ACK.
0x46 (hex), F (ascii) – fail NAK.
Description
The RTC Setup command setups, Initializes
and runs the RTC clock, once the command
was sent, the first response byte RTC State of
this command will tell the new/current RTC
state.
Each time the SmartGPU chip comes out
from a power off/shutdown state and no
backup battery is placed on VBat pad, this
command must be called in order to setup,
initialize and run the RTC for the first time.
Once the RTC is setup and running,
consecutive calls to this command will always
return 0x01(running) in the RTC State reply
parameter, as the RTC is already setup and
running.
Is recommended to call this command at the
beginning of the application program: If the
RTC is Stopped, SmartGPU 2 chip will try to
initialize and setup the RTC if a crystal is
mounted on the board, once some
milliseconds have passed, if the RTC wasn’t
successfully initialized, SmartGPU 2 will reply
0x00(stopped) as RTC State parameter. If the
RTC is already configured and running: and
this command is called, SmartGPU 2 will
check RTC internal state and simply ignore the
command returning 0x01(running) as RTC
State reply parameter.
When an application needs time and date,
clock and calendar functions, the RTC
must be enabled, also the FAT commands
time and date related functions uses the
RTC data to correctly set timestamps.