Product Specs

Table Of Contents
49 TWI I
2
C compatible two-wire interface
Page
525
1
Figure 157: The TWI master reading data from a slave
49.6 Master repeated start sequence
A typical repeated start sequence is one in which the TWI master writes one byte to the slave followed by
reading M bytes from the slave. Any combination and number of transmit and receive sequences can be
combined in this fashion. Only one shortcut to STOP can be enabled at any given time.
The figure below illustrates a repeated start sequence where the TWI master writes one byte, followed by
reading M bytes from the slave without performing a stop in-between.
Figure 158: A repeated start sequence, where the TWI master writes one byte, followed by reading M
bytes from the slave without performing a stop in-between
B
M-1
M
A
ADDR
2
1
3
A
M-1
M
3
2
ADDR
ADDR
0
5
4
5
4
STOP
NACK
STOP
NACK
ACK
ACK
ACK
ACK
ACK
READ
START
ACK
ACK
ACK
READ
ACK
WRITE
START
START
2-W Lifeline
CPU Lifeline
CPU Lifeline
TWI
TWI Lifeline
TWI
STARTRX
STARTTX
SHORT
TXD = 0
BB
SUSPEND
RXDRDY
SUSPENDED
TXDSENT
SHORT
STARTRX
SHORT
SUSPEND
A = RXD
RESUME
BB
BB
SUSPEND
RXDRDY
SUSPENDED
SHORT
SHORT
BB
BB
SUSPEND
SUSPEND
RXDRDY
SUSPENDED
RXDRDY
SUSPENDED
M-1 = RXD
M-1 = RXD
SHORT
RESUME
SHORT
RESUME
BB
BB
STOP
STOP
RXDRDY
RXDRDY
M = RXD
M = RXD
STOPPED
STOPPED