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10. Silicon ID Read
Silicon ID read is an operation that reads the manufacturer code and device code information. "Table 6 Silicon ID
codes table" lists the silicon ID codes. The silicon ID read command is not accepted during writing.
Two methods are used for silicon ID reading. The first method involves inputting the 9Fh command: the setting is
completed with only the first bus cycle input, and in subsequent bus cycles the manufacturer code 62h and device
code 26h are repeatedly output in succession so long as the clock input is continued. Refer to "Figure 16-a Silicon
ID read 1" for the waveforms.
The second method involves inputting the ABh command. This command consists of the first through fourth bus
cycles, and the silicon ID can be read when 16 dummy bits and an 8-bit address are input after (ABh). When address
A0 is "0", the manufacturer code 62h is read in the fifth bus cycle, and the device code 26h is read in the sixth bus
cycle. "Figure 16-b Silicon ID read 2" shows the timing waveforms. If, after the manufacturer code or device code
has been read, the SCK input is continued, the manufacturer code and device code are output alternately with each
bus cycle. When address A0 is "1", reading starts with device code 26h in the fifth bus cycle.
Table 6 Silicon ID Codes
Address
A0
Output Code
Manufacturer code 0 62h
Device code 1 27h
The data is output starting with the falling clock edge of the fourth bus cycle bit 0, and silicon ID reading ends at the
rising CS
edge.
Figure 16-a Silicon ID Read 1
Figure 16-b Silicon ID Read 2
N N+1 N
CS
High Impedance
SiID SiID SiID
SCK
SO
SI
9Fh
15
MSB MSB MSB
0 1 2 3
4 5 6 7 8 2316
8CLK
Mode0
Mode3
N N+1 N
CS
High Impedance
SiID SiID SiID
SCK
SO
SI
Bh
dd. X X
15
MSB MSB MSB
0 1 2 3
4 5 6 7 8 2316 24 31 39 47
8CLK
Mode0
Mode3
32 40
