Step Technica MKY02, Руководство пользователя

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Chapter 4 Cascade Connection of MKY02
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Chapter 4 Cascade Connection of MKY02
This chapter describes the pin functions and how to connect pins required to design a “multiport HUB (with
nine or more ports) (refer to
“1.6 Port Addition to HUB” ) configured using multiple MKY02s” to be
inserted into the HLS.
4.1 Concepts of Port Addition
This section describes the concepts of port addition to a HUB using multiple HUB-ICs.
4.1.1 Port Addition by Stacking Method
To add HUB ports using multiple MKY02s (HUB-
ICs), “stacking” is suitable as shown in the Figure 4.1.
“Stacking” is to connect one port of the sattelite side to
the port 0 of the next MKY02.
The connection by “stacking” has the following
demerits:
(1) Time lag (refer to “1.7.1 Receiving and Send-
ing of Packets” ) increase in subsequent
stacked ports.
(2) One satellite side port of the MKY02 cannot be
used.
The increased time lag in the above (1) may be unuse-
ful especially for the HLS used by a user system
requiring high real-timeness.
In addition, some types of center ICs used in the HLS
into which a HUB is inserted have restrictions on the
“stacked” count, the number of available ports or the
number of actually insertable HUBs may not meet the
user system needs.