JDS Uniphase SKB Series, Руководство пользователя

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Application Notes 79
Figure 13 (high-speed master ~200 µs /STROBE pulse width) and Figure 14 (low-speed master --
~18ms /STROBE pulse width) are oscilloscope trace captures showing typical line toggling for a
master write cycle. These figures show the relationship between R/W, /SOP, and /STROBE input
lines and the BUSY output line during a five-byte command packet write to the SKB. Note that in
each scenario illustrated, the line toggling is identical and independent of the /STROBE pulse time.
Figure 13 (high-speed master ~200
µ
s /STROBE pulse width) and Figure 14 (low-speed master --
~18ms /STROBE pulse width) are oscilloscope trace captures showing typical line toggling for a
master write cycle. These figures show the relationship between R/W, /SOP, and /STROBE input
lines and the BUSY output line during a five-byte command packet write to the SKB. Note that in
each scenario illustrated, the line toggling is identical and independent of the /STROBE pulse time.
Figure 13: SKB enhanced mode 5-byte write (master to slave) – high-speed
The following actions correspond to numbered events in Figure 13:
1. The R/W line is pulled low to indicate write-to-SKB operation
2. The /SOP line is then asserted (low) to indicate the start of a command packet.
3. The BUSY line of the SKB switch is asserted (high) to indicate /SOP processing.
4. Binary data is written to the data lines (D0 to D7), and the /STROBE line is asserted (low) to indi-
cate to the SKB switch that the byte can be read.
5. The BUSY line transitions to the idle (low) state to indicate that the SKB switch has read the byte.