Step Technica MKY02, Руководство пользователя

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MKY02 User’s Manual
(for Hi-speed Link System)
3 - 6
3.2.2 Setting Cascade Clock and Baud Rate
The MKY02 uses three cascade
clocks: AX0, AX1, and AX2. It has
three cascade clock output pins:
AXS0, AXS1, and AXS2 (Fig. 3.2).
A cascade clock is generated from the
external clock supplied to the Xi pin
based on a division ratio determined
by the settings of the BPS0 and BPS1
pins.
Conform the settings of the BPS0 (pin
52) and BPS1 (pin 53) pins to the baud rates of the HLS system into which the HUB is inserted.
To use a cascade clock, connect the output signal of the AXS0 pin to
the AX0 pin, of the AXS1 pin to the AX1 pin, and of the AXS2 pin to
the AX2 pin, as shown in Figure 3.3.
Table 3-1 shows the output frequencies of cascade clocks from the
AXS0, AXS1, and AXS2 pins corresponding to the settings of the
BPS0 and BPS1 pins when connecting a 48-MHz external clock to the
Xi pin.
The configuration to input cascade clocks output from the pins of the MKY02 to the pins of
the MKY02 again enables cascade connection of the MKY02 described in
“Chapter 4
Cascade Connection of MKY02” . To design the “HUB with two to eight ports config-
ured using one MKY02”, connect the output signals as shown in Figure 3.3.
Table 3-1 Output Frequencies of Cascade Clocks
BPS1 pin BPS0 pin Baud rate AXS0 pin AXS1 pin AXS2 pin
Hi Hi 12 Mbps 48 MHz 12 MHz 6 MHz
Hi Lo 6 Mbps 24 MHz 6 MHz 3 MHz
Lo Hi 3 Mbps 12 MHz 3 MHz 1.5 MHz
Lo Lo 1.5 Mbps 6 MHz 1.5 MHz 750 kHz