<s>
The	O
Advanced	B-Language
Boolean	I-Language
Expression	I-Language
Language	I-Language
(	O
ABEL	B-Language
)	O
is	O
an	O
obsolete	O
hardware	O
description	O
language	O
(	O
HDL	O
)	O
and	O
an	O
associated	O
set	O
of	O
design	O
tools	O
for	O
programming	O
programmable	O
logic	O
devices	O
(	O
PLDs	O
)	O
.	O
</s>
<s>
ABEL	B-Language
includes	O
both	O
concurrent	O
equation	O
and	O
truth	O
table	O
logic	O
formats	O
as	O
well	O
as	O
a	O
sequential	O
state	O
machine	O
description	O
format	O
.	O
</s>
<s>
A	O
preprocessor	O
with	O
syntax	O
loosely	O
based	O
on	O
Digital	O
Equipment	O
Corporation	O
's	O
MACRO-11	B-Device
assembly	B-Language
language	I-Language
is	O
also	O
included	O
.	O
</s>
<s>
In	O
addition	O
to	O
being	O
used	O
for	O
describing	O
digital	O
logic	O
,	O
ABEL	B-Language
may	O
also	O
be	O
used	O
to	O
describe	O
test	O
vectors	O
(	O
patterns	O
of	O
inputs	O
and	O
expected	O
outputs	O
)	O
that	O
may	O
be	O
downloaded	O
to	O
a	O
hardware	O
PLD	O
programmer	O
along	O
with	O
the	O
compiled	O
and	O
fuse-mapped	O
PLD	O
programming	O
data	O
.	O
</s>
<s>
Other	O
PLD	O
design	O
languages	O
originating	O
in	O
the	O
same	O
era	O
include	O
CUPL	O
and	O
PALASM	B-Language
.	O
</s>
<s>
Since	O
the	O
advent	O
of	O
larger	O
field-programmable	B-Architecture
gate	I-Architecture
arrays	I-Architecture
(	O
FPGAs	B-Architecture
)	O
,	O
PLD-specific	O
HDLs	O
have	O
fallen	O
out	O
of	O
favor	O
as	O
standard	O
HDLs	O
such	O
as	O
Verilog	B-Language
and	O
VHDL	B-Language
gained	O
adoption	O
.	O
</s>
<s>
The	O
ABEL	B-Language
concept	O
and	O
original	O
compiler	O
were	O
created	O
by	O
Russell	O
de	O
Pina	O
of	O
Data	O
I/O	O
'	O
s	O
Applied	O
Research	O
Group	O
in	O
1981	O
.	O
</s>
<s>
The	O
work	O
was	O
continued	O
by	O
ABEL	B-Language
product	O
development	O
team	O
(	O
led	O
by	O
Dr.	O
Kyu	O
Y	O
.	O
Lee	O
)	O
and	O
included	O
Mary	O
Bailey	O
,	O
Bjorn	O
Benson	O
,	O
Walter	O
Bright	O
,	O
Michael	O
Holley	O
,	O
Charles	O
Olivier	O
,	O
and	O
David	O
Pellerin	O
.	O
</s>
<s>
After	O
a	O
series	O
of	O
acquisitions	O
,	O
the	O
ABEL	B-Language
toolchain	O
and	O
intellectual	O
property	O
were	O
bought	O
by	O
Xilinx	O
.	O
</s>
<s>
Xilinx	O
discontinued	O
support	O
for	O
ABEL	B-Language
in	O
its	O
ISE	B-Algorithm
Design	I-Algorithm
Suite	I-Algorithm
starting	O
with	O
version	O
11	O
(	O
released	O
in	O
2010	O
)	O
.	O
</s>
