Si1000/1/2/3/4/5
Table 24.5. SMBus Status Decoding With Hardware ACK Generation Disabled (EHACK = 0)
Next Status
Vector Expected
1000
-
1110
1110
1110
1100
1100
Values Read
ARBLOST
Current SMbus State
Typical Response Options
Values to
Write
ACKRQ
Status
Vector
Mode
ACK
1110
1100
0
0
0
0
X A master START was gener-
ated.
0
Load slave address + R/W into
SMB0DAT.
0
1
0
0
0
0
0
1
0
1
1
0
0
X 1100
X 1110
X -
X 1100
X -
X -
X 1110
X 1000
A master data or address byte Set STA to restart transfer.
was transmitted; NACK
Abort transfer.
received.
A master data or address byte Load next data byte into
was transmitted; ACK
SMB0DAT.
received.
End transfer with STOP.
0
0
1
Master Transmitter
End transfer with STOP and start 1
another transfer.
Send repeated START.
1
Switch to Master Receiver Mode 0
(clear SI without writing new data
to SMB0DAT).
1000 1
0
X A master data byte was
received; ACK requested.
Acknowledge received byte;
Read SMB0DAT.
0
0
1
1
1
0
0
Send NACK to indicate last byte, 0
and send STOP.
Send NACK to indicate last byte, 1
and send STOP followed by
START.
Send ACK followed by repeated 1
START.
Send NACK to indicate last byte, 1
and send repeated START.
Master Receiver
Send ACK and switch to Master 0
Transmitter Mode (write to
SMB0DAT before clearing SI).
Send NACK and switch to Mas- 0
ter Transmitter Mode (write to
SMB0DAT before clearing SI).
0
0
0
1
0
1
0
0
306
Rev. 1.0
ACK
STO
STA
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