2009 Microchip Technology Inc.
DS39636D-page 185
PIC18F2X1X/4X1X
FIGURE 16-22:
I2C MASTER MODE WAVEFORM (RECEPTION, 7-BIT ADDRESS)
P
9
8
7
6
5
D0
D1
D2
D3
D4
D5
D6
D7
S
A7
A6
A5
A4
A3
A2
A1
SDA
SCL
12
3
4
5
6
7
8
9
12
3
45
67
8
9
12
3
4
B
u
sm
aster
ter
m
inate
s
tra
n
sfer
ACK
Re
ce
ivin
g
Da
ta
fr
o
m
Sl
av
e
Re
ce
ivin
gDa
ta
fr
om
Sla
ve
D0
D1
D2
D3
D4
D5
D6
D7
ACK
R/W
=
0
T
ra
n
smi
tA
ddr
ess
to
S
lave
SSPI
F
BF
AC
K
is
not
sent
W
ri
te
to
S
P
C
ON
2<
0>
(S
E
N
=
1
)
W
ri
te
to
S
P
B
U
F
occu
rs
her
e,
A
C
K
fr
o
m
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a
ve
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a
ster
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gured
as
a
r
e
cei
ver
by
pro
g
ram
m
ing
S
P
C
ON
2<
3>
(R
C
E
N
=
1
)
PE
N
b
it=
1
w
ri
tte
n
her
e
D
a
ta
sh
ifte
d
in
on
fal
ling
ed
ge
of
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K
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lear
ed
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ar
e
st
ar
tX
M
IT
SEN
=
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V
SDA
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0
,S
C
L
=
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ile
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(S
S
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T
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Cle
a
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d
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re
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ea
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re
S
et
S
P
IF
in
terr
upt
at
en
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r
e
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ve
Se
tP
b
it
(SSP
ST
A
T
<4
>)
an
d
S
P
IF
A
C
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m
Ma
ster
Se
tSS
PI
F
a
te
nd
S
e
tS
S
P
IF
inter
rup
t
at
end
o
fA
cknow
ledge
se
quence
Se
tSS
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F
in
te
rr
u
p
t
at
e
nd
of
A
ckno
w
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ledge
seque
nce
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r
e
ceive
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e
tA
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,st
ar
tA
cknow
ledg
e
sequ
ence
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D
A
=
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D
T
=
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RCEN
cle
a
re
d
au
tom
a
tically
RCEN
=
1
,st
ar
t
ne
xt
r
e
ce
ive
W
rite
to
S
P
C
ON2<
4>
to
st
ar
tA
cknowledge
seque
n
ce
SD
A
=
ACK
D
T
(
SSP
CO
N2
<5
>)
=
0
RCEN
cle
a
re
d
au
tom
a
tically
re
spond
sto
S
P
IF
ACKEN
B
e
gi
n
S
tar
tcond
iti
o
n
C
lear
ed
in
so
ftw
ar
e
SDA
=
A
C
KDT
=
0
Cle
a
re
d
in
sof
twar
e
La
st
bit
is
shif
ted
into
S
P
S
R
and
con
tent
sar
e
unl
o
aded
in
to
S
P
B
U
F
S
P
O
V
is
set
beca
use
S
SPB
UF
is
still
fu
ll