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Altera_Forum's avatar
Altera_Forum
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13 years ago

how to correctly assign to these variables

1. Error (10500): VHDL syntax error at tether2.vhd(152) near text "IN"; expecting an identifier ("in" is a reserved keyword), or a string literal constant ff_tx_mod : IN STD_LOGIC_VECTOR...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
13 years ago

Hi,

The Ethernet preamble is 14 instances of 0x5 (binary 0101), for which you'll need 7 bytes. This can be written many different ways in VHDL, but to write it as hex use:

x"55555555555555"

which is interpreted as an unsigned vector. You could also write it as:

16#55555555555555#

which is interpreted as an integer literal.

Mark.