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Altera_Forum
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13 years ago

Source-Synch I/O Constraints

I've read just about every post by Rysc and Kaz on constraints. Many thanks for their contributions to this forum. I'm having trouble getting the constraints right for a source synchronous int...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
13 years ago

I generally don't use the pre-canned I/O analysis, but create my own TQ_analysis.tcl file and put stuff in like so:

report_timing -setup -npaths 50 -detail full_path -to [get_ports {m_data_p[*]}] -panel_name "m_data_p||setup"

report_timing -hold -npaths 50 -detail full_path -to [get_ports {m_data_p[*]}] -panel_name "m_data_p||hold"

I do it for most interfaces and so the reports are tailored to those interfaces. (Anything you miss still shows up in the summary/hold/recovery/removal reports, so if something failed you'd know about it). Now if the above says no paths exist, it needs to be analyzed why. (I'm not sure on first glance, but fixing the create_generated_clock shouldn't have broken anything. Did the paths show up before?