Data Sheet

SD2405ALPI IIC 串行接口的实时时钟IC
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Data is written into the slave from the master
When data is read from the slave immediately after 7bit addressing from the master
When the transmission direction is to be changed during transmission
(3)Data Transmission Write Format in the SD2405AL
1）First send 7 address bit(0110010), the eighth bit is write command “0”. when the
ninth bit is ACK signal, SD2405AL is under writing condition.
2) In the following byte, the low 5 bits are determined as internal address in
SD2405AL(00H-1FH), the high 3 bits are transmission
mode .
3） After writing 1 byte data, there will be 1 bit ACK signal and then writing data in
next 1 byte starts. Only when there is a stop signal in the bit after ACK signal,
can the writing operation be stopped.
Example of data writing (When writing to internal address 14H to 15H)
(4)Data Transmission Read Format in the SD2405AL
The SD2405AL allows the following two readout methods of data from an internal register.
Ⅰ）The first method to reading data from the named internal address
1) The first two steps are the same as write mode.after one bit ACK signal, a new
start signal will be produced to change the direction of data transmission in
INTERFACE connection.
2) Then send 7 address bit(0110010), the eighth bit command is “1”, SD2405AL is under