¡ Semiconductor
MSM9810
7-2 Serial Input Interface
In the serial input interface, the microcomputer controls the LSI via 8 pins of RESET, CMD, CS,
WR, RD, SD, SI and SO. In parallel input, data is output from D7-D0, but in serial input, data for
D7-D0 is input in serial from MSB using SD and SI.
Figure 7-3 shows the command and subcommand input timing, and Figure 7-4 shows read
timing.
CMD(I)
tDW
tDW
tCC
CS(I)
tCW
tCW
WR(I)
SD(I)
SI(I)
tSDS
tSSD
tW(SCK)
Figure 7-3 Serial input write cycle timing
CS(I)
tCR
tCR
RD(I)
SO(I)
SI(I)
Figure 7-4 Serial input read cycle timing
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