<s>
The	O
PIC16C84	B-Device
,	O
PIC16F84	B-Device
and	O
PIC16F84A	B-Device
are	O
8-bit	O
microcontrollers	B-Architecture
of	O
which	O
the	O
PIC16C84	B-Device
was	O
the	O
first	O
introduced	O
in	O
1993	O
and	O
hailed	O
as	O
the	O
first	O
PIC	B-Architecture
microcontroller	I-Architecture
to	O
feature	O
a	O
serial	O
programming	O
algorithm	O
and	O
EEPROM	B-General_Concept
memory	O
.	O
</s>
<s>
It	O
is	O
a	O
member	O
of	O
the	O
PIC	B-Architecture
family	O
of	O
controllers	O
,	O
produced	O
by	O
Microchip	O
Technology	O
.	O
</s>
<s>
The	O
memory	O
architecture	O
makes	O
use	O
of	O
bank	B-General_Concept
switching	I-General_Concept
.	O
</s>
<s>
The	O
PIC16x84	B-Device
is	O
a	O
microcontroller	B-Architecture
in	O
the	O
PIC	B-Architecture
family	O
of	O
controllers	O
produced	O
by	O
Microchip	O
Technology	O
(	O
originally	O
named	O
"	O
Arizona	O
Microchip	O
"	O
)	O
.	O
</s>
<s>
It	O
was	O
Microchip	O
's	O
first	O
microcontroller	B-Architecture
that	O
utilised	O
"	O
EEPROM	B-General_Concept
"	O
memory	O
technology	O
for	O
the	O
program	O
memory	O
.	O
</s>
<s>
The	O
use	O
of	O
"	O
EEPROM	B-General_Concept
"	O
technology	O
for	O
program	O
memory	O
has	O
now	O
been	O
disused	O
in	O
favour	O
of	O
"	O
FLASH	O
"	O
memory	O
that	O
is	O
considerably	O
cheaper	O
to	O
manufacture	O
,	O
releases	O
less	O
toxins	O
into	O
the	O
atmosphere	O
and	O
is	O
much	O
more	O
reliable	O
than	O
"	O
EEPROM	B-General_Concept
"	O
.	O
</s>
<s>
Both	O
"	O
EEPROM	B-General_Concept
"	O
and	O
"	O
FLASH	O
"	O
utilise	O
similar	O
forms	O
of	O
"	O
floating	O
gate	O
"	O
technologies	O
to	O
operate	O
.	O
</s>
<s>
The	O
PIC16x84	B-Device
became	O
popular	O
in	O
many	O
hobbyist	O
applications	O
because	O
it	O
uses	O
a	O
serial	O
programming	O
algorithm	O
that	O
lends	O
itself	O
to	O
very	O
simple	O
programmers	O
.	O
</s>
<s>
Additionally	O
,	O
the	O
PIC16C84	B-Device
uses	O
EEPROM	B-General_Concept
memory	O
,	O
so	O
it	O
is	O
easy	O
to	O
erase	O
and	O
requires	O
no	O
special	O
tools	O
to	O
do	O
so	O
.	O
</s>
<s>
The	O
PIC16F84	B-Device
and	O
its	O
updated	O
version	O
,	O
the	O
PIC16F84A	B-Device
both	O
utilised	O
FLASH	O
program	O
memory	O
.	O
</s>
<s>
The	O
PIC16C84	B-Device
,	O
PIC16C84A	O
,	O
PIC16F84	B-Device
and	O
the	O
PIC16F84A	B-Device
all	O
contain	O
an	O
additional	O
64	O
Bytes	O
of	O
EEPROM	B-General_Concept
addressed	O
from	O
the	O
"	O
DATA	O
"	O
memory	O
map	O
.	O
</s>
<s>
The	O
PIC16F84/PIC16F84A	O
is	O
an	O
improved	O
version	O
of	O
the	O
PIC16C84	B-Device
,	O
and	O
almost	O
completely	O
compatible	O
,	O
with	O
better	O
program	O
security	O
and	O
using	O
flash	B-Device
memory	I-Device
instead	O
of	O
EEPROM	B-General_Concept
memory	O
for	O
program	O
memory	O
.	O
</s>
<s>
The	O
PIC16F84/PIC16F84A	O
has	O
68	O
bytes	O
of	O
RAM	O
whilst	O
the	O
PIC16C84	B-Device
has	O
36	O
bytes	O
.	O
</s>
<s>
Since	O
the	O
two	O
chips	O
are	O
so	O
similar	O
they	O
are	O
often	O
referred	O
to	O
by	O
the	O
term	O
PIC16x84	B-Device
(	O
x	O
is	O
used	O
as	O
a	O
wildcard	B-Algorithm
when	O
referring	O
to	O
chips	O
)	O
.	O
</s>
<s>
The	O
PIC16C84	B-Device
was	O
introduced	O
in	O
1993	O
and	O
has	O
been	O
hailed	O
as	O
the	O
first	O
PIC	B-Architecture
microcontroller	I-Architecture
to	O
feature	O
a	O
serial	O
programming	O
algorithm	O
and	O
EEPROM	B-General_Concept
memory	O
(	O
it	O
was	O
preceded	O
by	O
the	O
Motorola	O
MC68HC805B6	B-Device
and	O
MC68HC805C4	O
along	O
with	O
the	O
MC68HC11E2	O
with	O
serial	O
bootloader	O
and	O
EEPROM	B-General_Concept
program	O
storage	O
released	O
in	O
the	O
late	O
1980s	O
)	O
.	O
</s>
<s>
As	O
PIC16C84	B-Device
supplies	O
became	O
limited	O
due	O
to	O
it	O
being	O
discontinued	O
,	O
the	O
PIC16F84	B-Device
became	O
popular	O
as	O
it	O
is	O
an	O
almost	O
drop-in	O
replacement	O
.	O
</s>
<s>
Even	O
later	O
(	O
1998	O
)	O
Microchip	O
Technology	O
introduced	O
the	O
improved	O
PIC16F84A	B-Device
which	O
allowed	O
for	O
faster	O
clock	O
speeds	O
(	O
up	O
to	O
20MHz	O
)	O
,	O
faster	O
programming	O
,	O
and	O
decreased	O
the	O
current	O
draw	O
of	O
the	O
chip	O
.	O
</s>
<s>
The	O
PIC16x84	B-Device
microcontroller	B-Architecture
is	O
a	O
member	O
of	O
Microchip	O
's	O
14-bit	O
series	O
(	O
the	O
instruction	O
word	O
size	O
is	O
14	O
bits	O
for	O
all	O
instructions	O
)	O
,	O
making	O
the	O
'	O
84	O
a	O
good	O
development	O
prototype	O
for	O
other	O
similar	O
but	O
cheaper	O
one-time-programmable	B-General_Concept
14-bit	O
devices	O
.	O
</s>
<s>
Existing	O
PIC	B-Architecture
16x84	O
code	O
may	O
require	O
some	O
modifications	O
for	O
these	O
variants	O
,	O
namely	O
making	O
sure	O
pins	O
with	O
multiple	O
functions	O
have	O
been	O
set	O
up	O
properly	O
.	O
</s>
<s>
PIC	B-Architecture
16F628A	O
-	O
2K	O
program	O
memory	O
,	O
224	O
bytes	O
data	O
memory	O
,	O
128	O
bytes	O
EEPROM	B-General_Concept
,	O
3×	O
timers	O
,	O
hardware	O
PWM	O
,	O
onboard	O
4MHz/37kHz	O
RC	O
oscillator	O
.	O
</s>
<s>
PIC	B-Architecture
16F648A	O
-	O
Same	O
as	O
16F628A	O
with	O
4K	O
program	O
memory	O
.	O
</s>
<s>
PIC	B-Architecture
16F88	O
-	O
Nanowatt	O
Technology	O
variant	O
,	O
4K	O
program	O
memory	O
,	O
368	O
bytes	O
data	O
memory	O
,	O
256	O
bytes	O
EEPROM	B-General_Concept
,	O
3×	O
timers	O
,	O
hardware	O
PWM	O
,	O
on-board	O
8MHz/37kHz	O
precision	O
oscillator	O
,	O
7-input	O
10-bit	O
ADC	O
,	O
synchronous	O
serial	O
port	O
supporting	O
SPI	B-Architecture
and	O
I²C	O
.	O
</s>
<s>
PIC	B-Architecture
16F1827	O
-	O
Nanowatt	O
XLP	O
Technology	O
variant	O
,	O
4K	O
program	O
memory	O
,	O
368	O
bytes	O
data	O
memory	O
,	O
256	O
bytes	O
EEPROM	B-General_Concept
,	O
5×	O
timers	O
,	O
hardware	O
PWM	O
,	O
onchip	O
32MHz/31kHz	O
precision	O
oscillator	O
,	O
12-input	O
10-bit	O
ADC	O
,	O
4×	O
PLL	O
.	O
</s>
<s>
PIC	B-Architecture
16F1847	O
-	O
Nanowatt	O
XLP	O
Technology	O
variant	O
,	O
8K	O
program	O
memory	O
,	O
1024	O
bytes	O
data	O
memory	O
,	O
256	O
bytes	O
EEPROM	B-General_Concept
,	O
5×	O
timers	O
,	O
hardware	O
PWM	O
,	O
onchip	O
32MHz/31kHz	O
precision	O
oscillator	O
,	O
12-input	O
10-bit	O
ADC	O
,	O
4×	O
PLL	O
.	O
</s>
<s>
This	O
is	O
an	O
8-bit	O
enhanced	O
mid-range	O
core	O
with	O
14	O
additional	O
instructions	O
and	O
optimizations	O
for	O
the	O
C	B-Language
Programming	I-Language
Language	I-Language
.	O
</s>
