EP3SE50F780I3N Altera, EP3SE50F780I3N Datasheet - Page 430

• Manufacturer Part Number: EP3SE50F780I3N
• Description: Stratix III
• Manufacturer: Altera

Dedicated Remote System Upgrade Circuitry
Dedicated
Remote System
Upgrade
Circuitry
12–8
Stratix III Device Handbook, Volume 1
functional problem or if the system hangs, the dedicated circuitry will
update the remote system upgrade status register, triggering the loading
of the factory configuration.
1
If there is an error while loading the application configuration, the cause
of the reconfiguration is written by the dedicated circuitry to the remote
system upgrade status register. Actions that cause the remote system
upgrade status register to be written are:
■
■
■
■
Stratix III devices automatically load the factory configuration located at
page address zero. This user-designed factory configuration reads the
remote system upgrade status register to determine the reason for the
reconfiguration. The factory configuration then takes appropriate error
recovery steps and writes to the remote system upgrade control register
to determine the next application configuration to be loaded.
When Stratix III devices successfully load the application configuration,
they enter into user mode. In user mode, the soft logic (Nios II processor
or state machine and the remote communication interface) assists the
Stratix III device in determining when a remote system update is
arriving. When a remote system update arrives, the soft logic receives the
incoming data, writes it to the configuration memory device, and triggers
the device to load the factory configuration. The factory configuration
reads the remote system upgrade status register and control register,
determines the valid application configuration to load, writes the remote
system upgrade control register accordingly, and initiates system
reconfiguration.
This section explains the implementation of the Stratix III remote system
upgrade dedicated circuitry. The remote system upgrade circuitry is
implemented in hard logic. This dedicated circuitry interfaces to the
user-defined factory and application configurations implemented in the
Stratix III device logic array to provide the complete remote configuration
solution. The remote system upgrade circuitry contains the remote
system upgrade registers, a watchdog timer, and a state machine that
controls those components.
upgrade block's data path.
nSTATUS driven low externally
Internal CRC error
User watchdog timer time out
A configuration reset (logic array nCONFIG signal or external
nCONFIG pin assertion to low)
The user watchdog timer is automatically disabled for factory
configurations. For more information about the user watchdog
timer, refer to
“User Watchdog Timer” on page
Figure 12–5
shows the remote system
Altera Corporation
12–14.
October 2007