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Altera_Forum
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17 years ago

Pull-ups/Pull-Down/Slew-Rate I/O pins definitions

Hello, Scoured the Quartus/Cyclone-III docs for methods of defining Pull-ups/Pull-Down/Slew-Rate for I/O pins, but to no avail. 1. I understand that most of the device's I/O have interna...
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Altera_Forum
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17 years ago

Thanks you very much for the clear and precise info !

A few questions remain:

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The weak pull-ups are allways enabled, before the user defined FPGA configuration is in effect but disabled when the configuration gets active by default.

The default behaviour can be changed to enable the weak pull-up also in user mode, e. g. for an input that reads a configuration switch or to set a bidirectional bus to a defined state....

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1. Does this mean that, when in default behavior, there are always 'weak pull-ups' BEFORE & AFTER Configuration ('user mode'), but not during ?

2. And, how can this default behavior be changed ?