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Altera_Forum
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15 years ago

interface object "USB_RD_N" of mode out cannot be read

hello, i got a problem in my VHDL program. i have this error on an entry "USB_RD_N": "interface object "USB_RD_N" of mode out cannot be read. Change object mode to buffer. " My program descr...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
15 years ago

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Using a buffer in stead of an out just to fix the reading back issue is not recommended.

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The statement isn't understandable, if you suggest VHDL 2008 and it's implicite buffer function at the same time. Who doesn't recommend it and why?

Do you expect any differences in synthesized logic between copying an internal signal to the output port, a buffer port and a VHDL 2008 output port?