AR# 2866: 1.3 :GSR and GTS pads don't work in SXNF netlists from Synopsys for CPLDs.
AR# 2866
1.3 :GSR and GTS pads don't work in SXNF netlists from Synopsys for CPLDs.
描述
Keywords: GSR, GTS, sxnf
Urgency: standard
General Desription:
Explicit global Set/Reset(GSR) or global tristate(GTS) input pads do not work for CPLD designs if you use the Synopsys Design Compiler or the FPGA Compiler to write out XNF(.sxnf) netlists.
The global pads are normally specified either by using the set_pad_type -exact BUFGSR|BUFGTS dc shell command or by instantiating BUFGSR/BUFGTS cells in place of IBUFs. These cells are erroneously interpreted as global clock buffers(BUFG) during fitting and are ignored.
解决方案
Use EDIF-formatted netlists (.sedif) for all Synopsys CPLD designs in M1. All normal methods for specifying global buffers work ok via EDIF.