133 reset out behavior – Intel NETWORK PROCESSOR IXP2800 User Manual

Page 365

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Hardware Reference Manual

365

Intel

®

IXP2800 Network Processor

Clocks and Reset

“reset_out_strap” is sampled as 0 on the trailing edge of reset, nRESET_OUT is de-asserted based
on the value of IXP_RESET_0[15] which is written by software. If “reset_out_strap” is sampled as

1 on the trailing edge of reset, nRESET_OUT is de-asserted after PLL locks.

During normal function mode, if software wants to pull nRESET_OUT high, it should set

IXP_RESET_0[22] = 1 and then set IXP_RESET_0[15] = 1. To pull nRESET_OUT low, software
should set the IXP_RESET_0[15] bit back to 0.

Figure 133. Reset Out Behavior

A9780-01

PLL

Lock Signal

EXTRST_EN

RESET_OUT

RESET_OUT_STRAP

0

1

1

0

EXTRST

IXP_RESET0

Register

[15]

[22]

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