Philips Semiconductors
Preliminary specification
80C51 8-bit microcontroller
8K/256 OTP, 8 channel 10 bit A/D, I2C, PWM,
capture/compare, high I/O, low voltage (2.7V–5.5V), low power
P87C552
Table 6.
Master Transmitter Mode
APPLICATION SOFTWARE RESPONSE
STATUS
CODE
(S1STA)
STATUS OF THE
I C BUS AND
SIO1 HARDWARE
2
TO S1CON
NEXT ACTION TAKEN BY SIO1 HARDWARE
TO/FROM S1DAT
STA STO
SI
AA
08H
10H
A START condition has
been transmitted
Load SLA+W
X
0
0
X
SLA+W will be transmitted;
ACK bit will be received
Load SLA+W or
Load SLA+R
X
X
0
0
0
0
X
X
As above
SLA+W will be transmitted;
SIO1 will be switched to MST/REC mode
A repeated START
condition has been
transmitted
Load data byte or
0
0
0
X
Data byte will be transmitted;
ACK bit will be received
Repeated START will be transmitted;
STOP condition will be transmitted;
STO flag will be reset
STOP condition followed by a
START condition will be transmitted;
STO flag will be reset
18H
20H
28H
30H
38H
SLA+W has been
transmitted; ACK has
been received
no S1DAT action or
no S1DAT action or
1
0
0
1
0
0
X
X
no S1DAT action
1
1
0
X
Load data byte or
0
0
0
X
Data byte will be transmitted;
ACK bit will be received
Repeated START will be transmitted;
STOP condition will be transmitted;
STO flag will be reset
STOP condition followed by a
START condition will be transmitted;
STO flag will be reset
SLA+W has been
transmitted; NOT ACK
has been received
no S1DAT action or
no S1DAT action or
1
0
0
1
0
0
X
X
no S1DAT action
1
1
0
X
Load data byte or
0
0
0
X
Data byte will be transmitted;
ACK bit will be received
Repeated START will be transmitted;
STOP condition will be transmitted;
STO flag will be reset
STOP condition followed by a
START condition will be transmitted;
STO flag will be reset
Data byte in S1DAT has
been transmitted; ACK
has been received
no S1DAT action or
no S1DAT action or
1
0
0
1
0
0
X
X
no S1DAT action
1
1
0
X
Load data byte or
0
0
0
X
Data byte will be transmitted;
ACK bit will be received
Repeated START will be transmitted;
STOP condition will be transmitted;
STO flag will be reset
STOP condition followed by a
START condition will be transmitted;
STO flag will be reset
Data byte in S1DAT has
been transmitted; NOT
ACK has been received
no S1DAT action or
no S1DAT action or
1
0
0
1
0
0
X
X
no S1DAT action
1
1
0
X
2
No S1DAT action or
No S1DAT action
0
1
0
0
0
0
X
X
I C bus will be released;
Arbitration lost in
SLA+R/W or
Data bytes
not addressed slave will be entered
A START condition will be transmitted when the
bus becomes free
43
1999 Mar 30
NXP [ NXP ]
