ep3c120f780c8nes Altera Corporation, ep3c120f780c8nes Datasheet - Page 286

• Manufacturer Part Number: ep3c120f780c8nes
• Description: Cyclone Iii Device Family
• Manufacturer: Altera Corporation

Configuring Cyclone III Devices
10–50
Cyclone III Device Handbook, Volume 1
f
The MAX II device can also monitor the CONF_DONE and INIT_DONE
pins to ensure successful configuration. The CONF_DONE pin must be
monitored by the MAX II device to detect errors and determine when
programming completes. If all configuration data is sent, but CONF_DONE
or INIT_DONE have not gone high, the MAX II device must reconfigure
the target device.
1
When the device is in user-mode, you can initiate a reconfiguration by
transitioning the nCONFIG pin low-to-high. The nCONFIG pin must be
low for at least 500 µs. When nCONFIG is pulled low, the device also pulls
nSTATUS and CONF_DONE low and tri-states all I/O pins. Once nCONFIG
returns to a logic high level and nSTATUS is released by the device,
reconfiguration begins.
For more information about configuration issues, refer the Debugging
Configuration Problems chapter of the Configuration Handbook and the
FPGA Configuration Troubleshooter on the Altera web site at
www.altera.com.
Figure 10–15
device. This circuit is similar to the PS configuration circuit for a single
device, except Cyclone III devices are cascaded for multi-device
configuration.
If the optional CLKUSR pin is being used and nCONFIG is pulled
low to restart configuration during device initialization, you
need to ensure that CLKUSR continues toggling during the time
nSTATUS is low (maximum of 80 µs).
shows how to configure multiple devices using a MAX II
Altera Corporation-Preliminary
March 2007