EP3C55F780I7 Datasheet, PDF (235/274 Pages) Altera Corporation – This section provides a complete overview of all features relating to the Cyclone III device family

Chapter 9: Configuration, Design Security, and Remote System Upgrades in the Cyclone III Device Family
Remote System Upgrade
9–77
Configuration Image Types
When using remote system upgrade, Cyclone III device family configuration
bitstreams are classified as factory configuration images or application configuration
images. An image, also referred to as a configuration, is a design loaded into the
device that performs certain user-defined functions. Each device in your system
requires one factory image with the addition of one or more application images. The
factory image is a user-defined fall-back, or safe, configuration and is responsible for
administering remote updates with dedicated circuitry. Application images
implement user-defined functionality in the target Cyclone III device family. You can
include the default application image functionality in the factory image.
Remote System Upgrade Mode
In remote update mode, the Cyclone III device family loads the factory configuration
image after power-up. The user-defined factory configuration determines which
application configuration is to be loaded and triggers a reconfiguration cycle. The
factory configuration can also contain application logic.
When used with configuration memory, remote update mode allows an application
configuration to start at any flash sector boundary. Additionally, the remote update
mode features a user watchdog timer that can detect functional errors in an
application configuration.
Remote Update Mode
When a Cyclone III device family is first powered up in remote update in the AS
configuration scheme, it loads the factory configuration located at address
boot_address[23:0] = 24b'0. Altera recommends storing the factory configuration
image for your system at boot address 24b'0 when using the AS configuration
scheme. A factory configuration image is a bitstream for Cyclone III device family in
your system that is programmed during production and is the fall-back image when
an error occurs. This image is stored in non-volatile memory and is never updated or
modified using remote access. This corresponds to the start address location 0x000000
in the serial configuration device.
When you use the AP configuration in Cyclone III devices, the Cyclone III device
loads the default factory configuration located at the following address after device
power-up in remote update mode:
boot_address[23:0] = 24'h010000 = 24'b1 0000 0000 0000 0000
You can change the default factory configuration address to any desired address using
the APFC_BOOT_ADDR JTAG instruction. The factory configuration image is stored in
non-volatile memory and is never updated or modified using remote access. This
corresponds to the default start address location 0x010000 represented in 16-bit word
addressing (or the updated address if the default address is changed) in the
supported parallel flash memory. For more information about the application of the
APFC_BOOT_ADDR JTAG instruction in AP configuration scheme, refer to “JTAG
Instructions” on page 9–60.
August 2012 Altera Corporation
Cyclone III Device Handbook
Volume 1