Step Technica MKY02, Руководство пользователя

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MKY02 User’s Manual
(for Hi-speed Link System)
4 - 8
4.2.5 Selecting Communication Mode
When the specification for the HLS inserted the “port-added HUB” configured by cascade-connecting mul-
tiple MKY02s is full-duplex mode, fix the FH pin (pin 51) of all MKY02 at High. When the specification
indicates half-duplex mode, fix the FH pin at Low (Fig. 4.8). In addition, conform the specification for the
TRX (driver/receiver components) of the communication line connected to each port to the setting of the FH
pin.
The full-duplex mode and half-duplex mode cannot be mixed for cascade connection. Be
sure to select the same mode for the MKY02s to be cascade-connected.
4.2.6 Connection of Each Port
In the “port-added HUB” configured by cascade-connecting multiple MKY02s, connect the TRX to port 0
of the highest-priority MKY02 (refer to
“3.3.2 Connection of Port 0” ) and use it as a port to connect to
the center IC.
Leave the TXE0 pin (pin 62) and TXD0 pin (pin 63) of any MKY02 other than the highest-priority one
open.
Fix the RXD0 pin (pin 61) of any MKY02 other than the highest-priority one at a High or Low level.
Connect the TRX to each satellite port of multiple MKY02s (refer to
“3.3.3 Connection of Ports 1 to 7” )
and use it as a port to connect to the satellite IC. For the handling of unused ports, refer to “3.3.3 Connec-
tion of Ports 1 to 7” .
If multiple MKY02s are cascade-connected, ports are assigned priorities in descending order. Therefore,
number the satellite ports according to priority (Fig. 4.2).
Even if the TRX is connected to port 0 of any MKY02 other than the highest-priority one
like port 0 of the highest-priority MKY02, there is no problem because no packet is
received unless the communication lines are connected. This is effective when designing
circuit boards for the single connection and cascade connection to be shared.