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Altera_Forum
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15 years ago

ALT_INBUF_DIFF in cycloneII

is possible in cycloneII device use 2 pins INPUT for differential rs422 signal? In quartus2 the differential buffer for cyclone2 is not allowed!
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Altera_Forum
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15 years ago

hi std_logic_vector!

RS422 is not RS232.

It is a differential line (2 wires + ground) at level 0-3.3V.

it is compatible with ecl differential levels, but cycloneII has only dedicated pin for this function.

I can use the lvds standard on fpga, but it works at 2.5Volt, and i use in this bank register 3 pins at lvcmos level as output (3.3 volt).

regards