COMFILE CUTOUCH CT1820, Руководство пользователя

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Real-Time Clock
The CT1820 has a real-time clock (RTC) that can be used to measure calendar date and time. The
RTCWrite
command is used set the RTC's date and time, and the
RTCRead
command is used to read the
RTC's current date and time.
RTCRead( )
Variable = RTCRead( address )
v
ariable
: The variable to which the result will be stored
a
ddress
: RTC's register address
The following details the format of the data retrieved from the RTC.
Address BIT7 BIT6 BIT5 BIT4 BIT3 BIT2 BIT1 BIT0 Feature & Range
0 0 Seconds (10 1 ) Seconds (10 0 ) Seconds (0~59)
1 0 Minutes (10 1 ) Minutes (10 0 ) Minutes (0~59)
2 0 12/24 AM/PM Hours (10 1 ) Hours (10 0 ) Hours (0~23)
3 0 0 0 0 0 Day of the week 1~7
(1=Sun. ~ 7=Sat.)
4 0 0 Day (10 1 ) Day (10 0 ) Day (1~31)
5 Century 0 0 Month (10 1 ) Month (10 0 ) Month (1~12)
6 Year (10 1 ) Year (10 0 ) Year (0 ~ 99)
Address 0 stores the number of seconds in the RTC's current time. The data is stored as binary coded
decimal (BCD), so the first 4 bits store the 10 1 digit while the lower 4 bits store the 10 0 digit
Therefore, if address 0 stores the value 0001 0001
2
, then then the number of seconds is 11, not 17.
Displaying the value in hexadecimal, is one way to show the value in decimal as illustrated in the
example below.
A = RTCRead(0)
Debug Hex2 A,Cr
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