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clk input 50 MHz to pinE13 CycloneIII dev kit

Altera_Forum
Honored Contributor II
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Hi all learned members of the forum, 

 

I am writing a Verilog code to drive the 7-segment user display using clock signal to count 0 to 3 while selecting inputs from mux to selectively drive each digit of the 4-digit 7-segment display. This is part of my getting to know the board as well as learning digital concepts. In Modelsim and testbench, it's ok. 

 

My board: http://www.altera.com/products/devkits/altera/kit-cyc3.html 

 

My problem:  

Q1.) In the pin assignment, I narrowed down my option for clock to what I think is the simplest option. The 50 Mhz oscillator. The reference manual says signal propagates to pin E13 of the FPGA. But when I do "pin assignments", pin E13 does not exist in the list. Why? Did I miss something? 

 

Q2.) Because I could not get the 50 Mhz clk, I decided to use the 125 Mhz on board clk. But when I compile, there is this critical warning "found minimum pulse width or period violations". I guess my counter is counting too fast? Becuase when I implemented just the counter module, the same error message occurred.  

If so, please mention/point to me a technique to get the counter to count slower which I can try to implement. 

 

Thank you very much.
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Altera_Forum
Honored Contributor II
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--- Quote Start ---  

The reference manual says signal propagates to pin E13 of the FPGA. 

--- Quote End ---  

 

I see, that this is written in the manual. Actually E13 is a VCCIO8 pin. You may ask Altera for a correct version of the reference manual. 

 

P.S.: According to the schematic, CLKIN_50 is to PIN_AH15. There's also a cycloneIII_3c120_dev_quartus_pinouts example, that contains most relevant pinouts.
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Altera_Forum
Honored Contributor II
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But don't forget that the cycloneIII_3c120_dev_quartus_pinouts example has errors, as I said here (http://www.alteraforum.com/forum/showthread.php?t=2609)

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Altera_Forum
Honored Contributor II
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Thank you. 

For beginner, this can be confusing. 

But at least now I know I can check the pin info in ref manual against the schematics.
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Altera_Forum
Honored Contributor II
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Yes it's difficult. On this kit the only reliable source of information is the board schematics...

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