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Altera_Forum's avatar
Altera_Forum
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14 years ago

Proporgation delays using Quartus 2

I am using Quartus 2 for targeting a MAX7000S CPLD device; however I do not know how to view prorogation delays. I have a simple example, if a use a 2 input AND gate and look at the Timing output waveform it shows a delay of 10ns between input and output. However if I connect another gate after the first AND gate and look at the timing output waveform it still shows a 10ns delay between input and output. This cannot be correct as there are now 2 gate delays in the path between input and output. Could someone please offer me some advice on this issue, is there a way to set it up so it does show a gate delay for ever gate in the path? Thanks you very much in advance for your time.

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  • Altera_Forum's avatar
    Altera_Forum
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    It depends on how what you describe is synthesized. If your two gates can be combined in a single look-up table element inside the CPLD, then the delay will be exactly the same. Check in the report if the number of used resources is the same, or use the technology mapper to find out how Quartus converted your design to CPLD blocks.