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Altera_Forum's avatar
Altera_Forum
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12 years ago

LED toggle

I'm trying what I thought would be a very simple programme to turn alternate LEDs ON and OFF every half second, but it isn't working as it should. It starts off OK, with the LEDs toggling about every...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
12 years ago

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hi

thanks for the reply.

I'm not sure if I've 'solved' the problem, but I tried the 1 LED programme using each of the 4 different clock pins on the EPM240T100C5 CPLD, namely p12, p14, p62 and p64 and it would only work with p12. The LED didn't even light up using the other clock pins. Do you have to use the first clock pin on the chip if you only need 1 clock ? How do you tell Quartus what the speed is, I thought you only had to do that with an FPGA, but I'm happy to be corrected.

regards

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I assumed you are using timequest as your post suggested and so I wrote the sdc statement for clk in one of above replies.

If timequest does not support cpld then use the classic timing analyser and enter frequency in the relevant setting.

Then quartus will tell if you passed timing or not