Three-Byte Response Packet Read From Skb - High Speed - JDS Uniphase SKB Series User Manual

lines and the BUSY output line during a three-byte response packet read from the SKB. Note that in
each scenario illustrated, the line toggling is identical and independent of the /STROBE pulse time.
Figure 15: Three-byte response packet read from SKB – high speed
The following actions correspond to numbered events in Figure 15 and Figure 16:
1. The R/W line is driven high to indicate read-from-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 the first byte of the packet has
been written to the data bus.
4. Binary data is read from the data lines (D0 to D7) and the /STROBE line is asserted (low) to indi-
cate to the SKB switch that the byte was read.
5. The BUSY line is de-asserted (low) to indicate to the master that the SKB switch is ready to send
another byte.
6. The /STROBE is de-asserted (high) to indicate to the SKB switch that the master is ready to
accept another byte.
7. The BUSY is asserted (high) to indicate to the master that another byte has been written to the
data bus. All subsequent bytes are processed in the same fashion to indicate the master has
read the data bus.
8. The BUSY line is asserted (high) to indicate packet parsing and driven low when end-of-packet
processing is complete.
Application Notes 81