<s>
TLCS	O
is	O
a	O
prefix	O
applied	O
to	O
microcontrollers	B-Architecture
made	O
by	O
Toshiba	O
.	O
</s>
<s>
The	O
product	O
line	O
includes	O
multiple	O
families	O
of	O
CISC	B-Architecture
and	O
RISC	B-Architecture
architectures	I-Architecture
.	O
</s>
<s>
The	O
TLCS-12	O
was	O
a	O
12-bit	B-Device
microprocessor	B-Architecture
and	O
central	B-General_Concept
processing	I-General_Concept
unit	I-General_Concept
manufactured	O
by	O
Toshiba	O
.	O
</s>
<s>
It	O
was	O
a	O
32mm²	O
MOS	O
integrated	O
circuit	O
chip	O
with	O
about	O
2,800	O
silicon	O
gates	O
,	O
fabricated	B-Architecture
on	O
a	O
6	O
µm	O
process	O
with	O
NMOS	B-Algorithm
logic	I-Algorithm
.	O
</s>
<s>
It	O
was	O
used	O
in	O
the	O
Ford	O
EEC	O
engine	B-Device
control	I-Device
unit	I-Device
system	O
,	O
which	O
began	O
production	O
in	O
1974	O
and	O
went	O
into	O
mass	O
production	O
in	O
1975	O
.	O
</s>
<s>
The	O
system	B-General_Concept
memory	I-General_Concept
included	O
512-bit	O
RAM	B-Architecture
,	O
2kb	O
ROM	B-Device
and	O
2kb	O
EPROM	B-General_Concept
.	O
</s>
<s>
The	O
microcontrollers	B-Architecture
in	O
the	O
TLCS-47	O
category	O
are	O
4-bit	O
systems	O
.	O
</s>
<s>
The	O
TLCS-48	O
family	O
were	O
clones	O
of	O
the	O
Intel	B-Device
MCS-48	I-Device
(	O
8048	B-Device
)	O
microcontroller	B-Architecture
.	O
</s>
<s>
These	O
were	O
a	O
series	O
of	O
Zilog	B-General_Concept
Z80	I-General_Concept
compatible	O
microcontrollers	B-Architecture
.	O
</s>
<s>
The	O
microcontrollers	B-Architecture
in	O
the	O
TLCS-90	O
family	O
use	O
a	O
8-bit/16	O
-bit	O
architecture	O
reminiscent	O
of	O
the	O
Z80	B-General_Concept
.	O
</s>
<s>
The	O
TLCS-90	O
inherits	O
most	O
Z80	B-General_Concept
features	O
,	O
such	O
as	O
:	O
</s>
<s>
seven	O
8-bit	O
registers	O
(	O
A	O
,	O
B	O
,	O
C	B-Language
,	O
D	O
,	O
E	O
,	O
H	O
and	O
L	O
)	O
,	O
</s>
<s>
six	O
16-bit	B-Device
registers	O
(	O
BC	O
,	O
DE	O
,	O
HL	O
,	O
IX	O
,	O
IY	O
,	O
and	O
SP	O
)	O
,	O
three	O
of	O
which	O
are	O
8-bit	O
register	O
pairs	O
,	O
</s>
<s>
It	O
omits	O
the	O
separate	O
I/O	O
address	O
space	O
of	O
the	O
Z80	B-General_Concept
,	O
but	O
adds	O
more	O
flexibility	O
to	O
operand	O
combinations	O
,	O
some	O
new	O
operations	O
(	O
notably	O
multiply	O
and	O
divide	O
)	O
,	O
and	O
several	O
additional	O
addressing	B-Language
modes	I-Language
:	O
</s>
<s>
Most	O
of	O
the	O
functionality	O
of	O
8-bit	O
accumulator	O
A	O
has	O
also	O
been	O
implemented	O
for	O
the	O
16-bit	B-Device
HL	O
register	O
pair	O
,	O
such	O
as	O
the	O
missing	O
and	O
instructions	O
,	O
and	O
the	O
,	O
,	O
and	O
bitwise	O
instructions	O
.	O
</s>
<s>
The	O
flag	O
quirk	O
from	O
the	O
Z80	B-General_Concept
is	O
implemented	O
.	O
</s>
<s>
Furthermore	O
,	O
the	O
instruction	O
was	O
added	O
to	O
ease	O
16-bit	B-Device
loop	O
counting	O
.	O
</s>
<s>
The	O
instruction	O
encoding	O
is	O
unusual	O
in	O
that	O
the	O
prefix	O
specifies	O
one	O
operand	O
of	O
the	O
extended	O
instruction	O
,	O
and	O
unlike	O
the	O
single-byte	O
prefixes	O
used	O
by	O
the	O
Z80	B-General_Concept
or	O
x86	B-Operating_System
architecture	I-Operating_System
,	O
may	O
itself	O
be	O
followed	O
by	O
operand	O
bytes	O
.	O
</s>
<s>
The	O
microcontrollers	B-Architecture
in	O
the	O
TLCS-870	O
family	O
(	O
TLCS-870	O
,	O
TLCS-870/X	O
,	O
TLCS-870/C	O
and	O
TLCS-870/C1	O
series	O
)	O
use	O
a	O
8-bit/16	O
-bit	O
architecture	O
inspired	O
by	O
the	O
TLCS-90	O
,	O
but	O
less	O
like	O
the	O
Z80	B-General_Concept
.	O
</s>
<s>
The	O
TLCS-870	O
is	O
the	O
original	O
,	O
with	O
a	O
16-bit	B-Device
address	O
space	O
,	O
which	O
was	O
extended	O
in	O
two	O
different	O
directions	O
:	O
</s>
<s>
TLCS-870/C	O
retains	O
the	O
16-bit	B-Device
address	O
space	O
,	O
and	O
provides	O
a	O
compatible	O
assembly	B-Language
language	I-Language
,	O
but	O
changes	O
the	O
instruction	O
encoding	O
so	O
that	O
a	O
different	O
object	B-Language
code	I-Language
is	O
required	O
.	O
</s>
<s>
TLCS-870/C1	O
is	O
an	O
upward-compatible	O
variant	O
of	O
the	O
870/C	O
with	O
minor	O
extensions	O
.	O
</s>
<s>
Most	O
implementations	O
(	O
TLCS-900	O
,	O
TLCS-900/L	O
,	O
TLCS-900/H	O
and	O
TLCS-900/L1	O
series	O
)	O
have	O
16-bit	B-Device
internal	O
data	O
paths	O
,	O
like	O
the	O
MC68000	B-Device
,	O
while	O
the	O
TLCS-900/H1	O
series	O
is	O
32	O
bits	O
wide	O
internally	O
(	O
like	O
the	O
MC68020	B-Device
)	O
.	O
</s>
<s>
The	O
same	O
scheme	O
of	O
encoding	O
the	O
addressing	B-Language
mode	I-Language
before	O
the	O
instruction	O
's	O
opcode	O
and	O
additional	O
operands	O
is	O
implemented	O
.	O
</s>
<s>
The	O
early	O
models	O
supported	O
both	O
a	O
"	O
minimum	O
mode	O
"	O
where	O
the	O
banked	O
registers	O
and	O
program	B-General_Concept
counter	I-General_Concept
were	O
16	B-Device
bits	I-Device
wide	O
,	O
and	O
a	O
"	O
maximum	O
mode	O
"	O
which	O
had	O
all	O
32-bit	O
general	O
purpose	O
registers	O
.	O
</s>
<s>
In	O
maximum	O
mode	O
,	O
there	O
are	O
4	O
banks	O
of	O
four	O
32-bit	O
registers	O
,	O
each	O
of	O
which	O
can	O
be	O
split	O
into	O
two	O
16-bit	B-Device
halves	O
or	O
four	O
8-bit	O
quarters	O
.	O
</s>
<s>
In	O
the	O
minimum	O
mode	O
of	O
early	O
models	O
,	O
there	O
are	O
8	O
banks	O
of	O
four	O
16-bit	B-Device
registers	O
,	O
which	O
can	O
be	O
split	O
into	O
8-bit	O
halves	O
.	O
</s>
<s>
The	O
processor	O
can	O
use	O
the	O
current	O
bank	O
(	O
pointed	O
to	O
by	O
the	O
field	O
in	O
the	O
16-bit	B-Device
status	O
register	O
SR	O
)	O
,	O
the	O
previous	O
bank	O
to	O
be	O
compatible	O
with	O
the	O
alternate	O
register	O
scheme	O
of	O
the	O
TLCS-90	O
,	O
or	O
any	O
arbitrary	O
bank	O
number	O
from	O
0	O
to	O
7	O
.	O
</s>
<s>
Normally	O
,	O
only	O
a	O
set	O
of	O
8	O
registers	O
can	O
be	O
addressed	O
from	O
a	O
3-bit	O
code	O
;	O
addressing	O
all	O
registers	O
requires	O
an	O
additional	O
6/8	O
-bit	O
code	O
byte	O
that	O
can	O
only	O
be	O
inserted	O
in	O
the	O
prefixed	O
addressing	B-Language
mode	I-Language
operand	O
,	O
restricting	O
which	O
combinations	O
of	O
registers	O
can	O
be	O
used	O
for	O
the	O
source	O
and	O
destination	O
operands	O
.	O
</s>
<s>
The	O
F	O
register	O
(	O
low	O
8-bit	O
half	O
of	O
the	O
16-bit	B-Device
register	O
SR	O
)	O
has	O
an	O
alternate	O
register	O
called	O
F	O
 '	O
.	O
</s>
<s>
These	O
are	O
triggered	O
the	O
same	O
way	O
as	O
normal	O
interrupts	B-Application
,	O
and	O
interrupt	B-Application
program	O
execution	O
upon	O
the	O
transferring	O
process	O
.	O
</s>
<s>
The	O
TLCS-900/H	O
model	O
was	O
most	O
prominently	O
used	O
in	O
the	O
Neo	B-Device
Geo	I-Device
Pocket	I-Device
and	O
Neo	B-Application
Geo	I-Application
Pocket	I-Application
Color	I-Application
.	O
</s>
<s>
mask	O
programmable	O
,	O
one	B-General_Concept
time	I-General_Concept
programmable	I-General_Concept
,	O
flash	B-Device
memory	I-Device
or	O
EEPROM	B-General_Concept
type	O
of	O
ROM	B-Device
.	O
</s>
<s>
Toshiba	O
offers	O
an	O
ANSI	O
C	B-Language
compatible	O
C	B-Language
compiler	B-Language
and	O
an	O
assembler	B-Language
.	O
</s>
<s>
The	O
free	O
Small	B-Application
Device	I-Application
C	I-Application
Compiler	I-Application
supports	O
the	O
TLCS-90	O
.	O
</s>
<s>
Alfred	O
Arnold	O
's	O
The	O
Macroassembler	B-Language
AS	O
is	O
a	O
free	O
assembler	B-Language
supporting	O
the	O
TLCS-47	O
,	O
TLCS-870	O
,	O
TLCS-90	O
,	O
TLCS-900	O
and	O
TLCS-9000	O
families	O
.	O
</s>
