Unit installation
MAX+PLUS II Getting Started
338 Altera Corporation
timing analysis displayed in the 
MAX+PLUS II Timing Analyzer. 
timing assignment An assignment that 
specifies desired speed performance on 
one or more logic functions. 
The t
PD
, t
SU
, t
CO
, and f
MAX
 timing 
assignments, as well as Òtiming cuts,Ó are 
available. You can assign timing to 
individual logic functions and specify 
default timing for the project as a whole. 
Timing assignments influence project 
compilation only for the FLEX 6000, 
FLEX 8000, and FLEX 10K device families.
timing cut A type of timing assignment 
that cuts the connections between the 
timing path for an individual node and 
other nodes in the project, to indicate that 
the Compiler should not consider the delay 
along this path when it attempts to meet 
the userÕs desired speed performance 
while processing the project.
t
PD
 (input to non-registered output delay)
The time required for a signal from an 
input pin to propagate through 
combinatorial logic and appear at an 
external output pin.
t
PD
 is also a timing assignment that 
specifies the maximum acceptable input to 
non-registered output delay. In 
MAX+PLUS II, you can specify a required 
t
PD
 for an entire project and/or for any 
input pin (INPUT or INPUTC), output pin 
(OUTPUT or OUTPUTC), or TRI buffer (i.e., 
BIDIR or BIDIRC pin output function) 
pin.
tri-state buffer A buffer with an input, 
output, and controlling Output Enable 
signal. If the Output Enable input is high, 
the output signal equals the input. If the 
Output Enable input is low, the output 
signal is in a state of high impedance. The 
tri-state buffer is implemented with the 
TRI primitive.
Tri-state buses can be implemented by 
tying multiple nodes together in a Graphic 
Editor file and with the TRI_STATE_NODE 
variable in an AHDL file.
t
SU
 (Clock setup time) The length of time 
for which data that feeds a register via its 
data or Enable input(s) must be present at 
an input pin before the Clock signal that 
clocks the register is asserted at the Clock 
pin.
t
SU
 is also a timing assignment that 
specifies the maximum acceptable Clock 
setup time. In MAX+PLUS II, you can 
specify a required t
SU
 for an entire project 
and/or for any input pin (INPUT or 
INPUTC) or bidirectional pin (BIDIR or 
BIDIRC input function).
TTF see Tabular Text File.
Turbo Bit and logic cell Turbo Bit A control 
bit for choosing speed and power 
characteristics of an Altera device. The 
Turbo Bit logic option is most effective 
when applied to megafunctions, 
macrofunctions, and pins. If the Turbo Bit 
is on, the speed increases; if it is off, the 
power consumption decreases. The Turbo 
Bit can be turned on or off in a design file or 
the Compiler. 
Turbo Bit availability differs for each 
device family
81_GSBOOK.fm5 Page 338 Tuesday, October 14, 1997 4:04 PM










