Forum Discussion
Altera_Forum
Honored Contributor
18 years agoThe uTsu is subtracted from the Data Required time. You seem to have a negative uTsu value in the case you show. Thus, Required = 10.254 - -40ps = 10.294. Most often you will see the uTsu subtracted in the TimeQuest reports.
+----------------------------------------------------------------------------------+ ; Data Required Path ; +-------+--------+----+------+--------+------------------+-------------------------+ ; Total ; Incr ; RF ; Type ; Fanout ; Location ; Element ; +-------+--------+----+------+--------+------------------+-------------------------+ ; 2.500 ; 2.500 ; ; ; ; ; latch edge time ; ; 2.500 ; 0.000 ; ; ; ; ; source latency ; ; 2.500 ; 0.000 ; ; ; 1 ; PIN_L22 ; clk ; ... ; 4.910 ; 0.000 ; ; ; ; ; clock uncertainty ; ; 4.831 ; -0.079 ; ; uTsu ; 1 ; FF_X52_Y24_N29 ; out_reg[6][7] ; +-------+--------+----+------+--------+------------------+-------------------------+