MINTERM(10.6) MINTERM(10.6)
NAME
minterm - minterm file format
DESCRIPTION
The minterm file format consists of at least one binary val-
ued function definition. A function definition begins .o
name[@flag*] [name]... followed by line(s) that have the
form term:mask ... Name is either a string or a number.
The first name following .o is a symbol of the function
(usually an output pin name or number of a ROM/PAL/FPGA
integrated circuit). Any other name's are symbols of input
binary variables. Term and mask are decimal numbers.
There is a correspondence between the bits of the numbers in
binary representation and the input symbols, the first input
symbol is associated with the least significant bit. The
meaning of a bit with value 1 in mask is `do care', and the
meaning of a bit with value 1 in term is `input must be 1'.
Thus the term:mask is an implicant, and a set of them when
or'ed together describes the input conditions for which the
output symbol will have a value of 1.
For example:
.o 3 1 2
3:3
.o 4 1 2
1:3 2:3 3:3
.o 5 2 3
1:3 2:3
.o 11
.o 9
0:0
Output 3 is the and function of inputs 1 and 2; output 4 is
the or function of inputs 1 and 2 (quine(10.1) would change
this to 1:1 2:2); output 5 is the exclusive-or function of
inputs 2 and 3; output 11 is a constant 0 and output 9 is a
constant 1.
Flag information is essentially communication between lde
and the technology mapper for a particular architecture, and
is passed through unchanged by quine, cover, and hazard (see
quine(10.1)). Among the flags are
b buried
d D flip-flop clock
e output enable
g clock enable
i inverted sense
t T flip-flop clock
Page 1 Plan 9 (printed 12/21/24)
MINTERM(10.6) MINTERM(10.6)
Another example:
.o x0@b
0:0
.o x1@b x0
1:1
.o x2@b x0 x1
3:3
.o x0@t ck
1:1
.o x1@t ck
1:1
.o x2@t ck
1:1
.o c2 x2
1:1
.o c2@e en
1:1
x[012] are bits of a buried three bit counter, each bit is
toggled by ck only if all lower bits are 1. c2 outputs x2,
the output enable is controlled by ck.
SEE ALSO
lde(10.1), quine(10.1), cover(10.1), hazard(10.1),
xpal(10.1), part(10.1), act(10.1)
Page 2 Plan 9 (printed 12/21/24)