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Old 01-05-2004, 08:05 PM
J.F. FOURCADIER
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Default Altera CPLD - Illegal assignment-global clock

Newbie

I try to use an Altera CPLD EPM7064. When I try to connect a register clock
input to a normal pin, I get the message "Illegal assignment-global
clock'input_clock' on pin 31.
I understand it's better to connect this kind of input on a dedicated clock
pin, but I cann't for wiring reasons.

The data sheet indicates a programmable register can be clocked by signals
from buried macrocells or I/O pins. How can I get this result ? I work on
the the graphic editor.

Thank you for your help !

Jean-François FOURCADIER, F4DAY

website : http://perso.wanadoo.fr/jf.fourcadier/





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  #2 (permalink)  
Old 01-05-2004, 10:41 PM
Mike Treseler
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Default Re: Altera CPLD - Illegal assignment-global clock

J.F. FOURCADIER wrote:

> The data sheet indicates a programmable register can be clocked by signals
> from buried macrocells or I/O pins. How can I get this result ? I work on
> the the graphic editor.


On the 7064, the only route to the internal
clocks is through the special pins.

You may have to bend up a pin
and solder a wire.

-- Mike Treseler

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  #3 (permalink)  
Old 01-05-2004, 11:50 PM
Dejan Durdenic
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Default Re: Altera CPLD - Illegal assignment-global clock

You have probably checked "Automatic Global Clock" in the "Global Project
Logic Synthesis"
window - that will assign your clock to the global clock input pin.Uncheck
it, and you can route
your clock where you like (although there will be a speed penalty, of
course).

- Dejan

"J.F. FOURCADIER" <[email protected]> wrote in message
news:[email protected]
> Newbie
>
> I try to use an Altera CPLD EPM7064. When I try to connect a register

clock
> input to a normal pin, I get the message "Illegal assignment-global
> clock'input_clock' on pin 31.
> I understand it's better to connect this kind of input on a dedicated

clock
> pin, but I cann't for wiring reasons.
>
> The data sheet indicates a programmable register can be clocked by signals
> from buried macrocells or I/O pins. How can I get this result ? I work on
> the the graphic editor.
>
> Thank you for your help !
>
> Jean-François FOURCADIER, F4DAY
>
> website : http://perso.wanadoo.fr/jf.fourcadier/
>
>
>
>
>



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