I just spent a little time googling, doing and debugging this. Thought I'd try and save anyone else the bother by posting this as a starting point. 'pos' is the number to display. 'servo_count' just counts.
Entity extract followed by VHDL process followed by UCF extract
entity top is port ( clock : in std_logic; --system clock res_n : in std_logic; --system clock DIGIT_ANODE : out std_logic_vector(3 downto --system clock SEGMENT : out std_logic_vector(7 downto --system clock ); end top;
led_driver : process(res_n, clock)
begin if res_n = '0' then digit