The following represent a collection of issues that have been identified in the
12.4 ISE Design Tools and are related to Spartan-6 FPGA. There might be issues which are present and are not listed here. If you discover an issue that is not on this list, please open a
WebCase with Xilinx Technical Support.
It is strongly recommended that designs be re-synthesized (and IP cores re-implemented) when re-implementing for production using the software that has production status speed files for the target device. This ensures that the changes to DRCs, timing models, clock topologies, and other fixes in softwareare picked up.
Configuration: (Xilinx Answer 36521) Spartan-6 Configuration - BPI configuration not supported in LX25/T devices
(Xilinx Answer 39582)Spartan-6 Design Advisory- When using POST_CONFIG_CRC the INIT_B pin can not be User I/O
(Xilinx Answer 38733) Spartan-6 - LX100/LX100T SMAP x16 max CCLK frequency reduction
GTP Transceivers: (Xilinx Answer 35237) Spartan-6 FPGA GTP Transceiver - SelectIO to GTP Crosstalk / SSO Guidelines
IODELAY2: (Xilinx Answer 38408) Spartan-6 Design Advisory - IODELAY2 -early edge delays, late edge delays,and single data bit corruption
PCI Express: (Xilinx Answer 37955) Spartan-6 FPGA Integrated Block Wrapper v2.1 for PCI Express - VHDL Wrapper Not Available for v2.1 Release
(Xilinx Answer 36416) Spartan-6 FPGA Integrated Block Wrapper v1.4 and v2.1 for PCI Express - User implemented configuration space registers starting addresses are not customizable
Timing Analysis: (Xilinx Answer 39545) 12.4 - Timing Analysis -ISE 12.4 does not support Spartan-6 -3 speed grade Engineering Sample (ES) devices
Additional Resources: (Xilinx Answer 34856) - Design Advisory for the Spartan-6 FPGA Master Answer Record
Spartan-6 Production Errata and
Product Change Notification (PCN)
Improving Performance in Spartan-6 FPGA Designs White Paper(WP311) Targeting and Re-targeting Guide for Spartan-6 FPGAs White Paper(WP309) Revision History 12/20/2010 - Updated complete list for 12.4 Known Issues
10/05/2010 - Updated complete list for 12.3 Known Issues
07/23/2010 - Updated complete list for 12.2 Known Issues
06/16/2010 - Added Answer Records 35978, 35976, 35818, 35044, and 36221
05/19/2010 - Added "Additional Resources" section
05/03/2010 - Initial 12.1 Release