C8051F980-C-GM Datasheet, PDF (255/325 Pages) Silicon Laboratories – Ultra Low Power, 8-2 kB Flash, Capacitive Sensing MCU

C8051F99x-C8051F98x
Table 22.6. SMBus Status Decoding With Hardware ACK Generation Enabled
(EHACK = 1)
Values Read
Values to
Write
Current SMbus State
Typical Response Options
1110
0
0
X
A master START was gener-
ated.
Load slave address + R/W into
SMB0DAT.
0 0 X 1100
A master data or address byte Set STA to restart transfer.
0 0 0 was transmitted; NACK
received.
Abort transfer.
1 0 X 1110
01X —
Load next data byte into SMB0-
DAT.
0 0 X 1100
End transfer with STOP.
01X —
1100
0
0
1
A master data or address byte
was transmitted; ACK
End transfer with STOP and start
another transfer.
1
1
X
—
received.
Send repeated START.
1 0 X 1110
Switch to Master Receiver Mode
(clear SI without writing new data
to SMB0DAT). Set ACK for initial
0
0
1
1000
data byte.
Set ACK for next data byte;
Read SMB0DAT.
0 0 1 1000
0
0
1
A master data byte was
received; ACK sent.
Set NACK to indicate next data
byte as the last data byte;
Read SMB0DAT.
Initiate repeated START.
0 0 0 1000
1 0 0 1110
1000
Switch to Master Transmitter
Mode (write to SMB0DAT before 0 0 X 1100
clearing SI).
Read SMB0DAT; send STOP. 0 1 0 —
A master data byte was
0 0 0 received; NACK sent (last
byte).
Read SMB0DAT; Send STOP
followed by START.
1 1 0 1110
Initiate repeated START.
1 0 0 1110
Switch to Master Transmitter
Mode (write to SMB0DAT before 0 0 X 1100
clearing SI).
Rev. 1.2
255