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Reset distribution, Starting configuration, Factory & user configurations – Altera Nios Development Board Cyclone II Edition User Manual

Page 48: R to, Figure 2–17

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2–36

Reference Manual

Altera Corporation

Nios Development Board Cyclone II Edition

May 2007

Board Components

Figure 2–17. Reset, Config Button

Reset Distribution

The EPM7256AE device takes a power-on reset pulse from the Linear
Technologies 1326 power-sense/reset-generator chip (U18) and
distributes it (through internal logic) to other reset pins on the board, that
include the following:

LAN91C111 (Ethernet MAC/PHY) reset

Flash memory reset

CompactFlash reset

Reset signals delivered to the expansion prototype connectors
(PROTO1 & PROTO2)

Starting Configuration

The following four methods start a configuration sequence:

1.

Board power-on

2.

Pressing the Reset, Config button (SW10).

3.

Asserting (driving 0 volts on) the

pld_reconfigreq_n input pin

of the EPM7256AE device (U3 pin 94) from the FPGA (U62 pin
AA14).

4.

Pressing the Factory Config button (SW9).

Factory & User Configurations

The configuration controller can manage two separate FPGA
configurations stored in flash memory U5. These two configurations are
referred to as the factory configuration and the user configuration. A

Reset,
Config

SW10