80221 datasheet(31/91 Pages) LSI

Part #	80221

Description	100BASE-TX/10BASE-T Ethernet Media Interface Adapter

PDF	91 Pages

Scroll/Zoom	100%

Manufacturer	LSI [LSI Computer Systems]

Direct Link	http://www.lsicsi.com

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31 / 91 page

80220/80221

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MD400159/E

INTERNAL

INTERRUPT

MDC

MDIO

MDIO HI-Z

PULLED HIGH EXTERNALLY

MDIO HI-Z

PULLED HIGH EXTERNALLY

INTERRUPT

PULSE

INTERNAL

INTERRUPT

MDC

MDIO

LAST TWO BITS

OF READ CYCLE

MDIO HI-Z

PULLED HIGH EXTERNALLY

INTERRUPT

PULSE

MDIO HI-Z

PULLED HIGH EXTERNALLY

Figure 10. MDIO Interrupt Pulse

this bit is set, an interrupt is signalled by an low going pulse

on MDIO when MDC is high and the serial port is in the idle

state, as shown in the timing diagram in Figure 10. Once

MDIO is forced low to indicate the interrupt condition,

MDIO stays low until MDC returns low. Once MDC returns

a.) Interrupt Happens During Idle.

b.) Interrupt Happens During Read Cycle.

low, then MDIO goes back to high impedance state. If the

interrupt occurs while the serial port is being accessed,

then the MDIO interrupt pulse is delayed until one clock bit

after the serial port access cycle is ended as shown in

Figure 10.

80221 Datasheet(PDF) 31 Page - LSI Computer Systems