C8051T610DK Silicon Laboratories Inc, C8051T610DK Datasheet - Page 144

• Manufacturer Part Number: C8051T610DK
• Description: KIT DEV FOR C8051T61X MCU'S
• Manufacturer: Silicon Laboratories Inc
• Type: MCUr

Specifications of C8051T610DK

• Contents: Board, daughter boards, power adapter, cables, documentation and software
• Processor To Be Evaluated: C8051T61x
• Interface Type: USB
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With/related Products: C8051T610
• For Use With: 336-1507 - DAUGHTER BOARD T610 24QFN SOCKET336-1506 - DAUGHTER BOARD T610 28QFN SOCKET336-1505 - DAUGHT BOARD T610 32TQFP SOCKET
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• Other names: 336-1443

C8051T610/1/2/3/4/5/6/7
22.5.2. Read Sequence (Master)
During a read sequence, an SMBus master reads data from a slave device. The master in this transfer will
be a transmitter during the address byte, and a receiver during all data bytes. The SMBus interface gener-
ates the START condition and transmits the first byte containing the address of the target slave and the
data direction bit. In this case the data direction bit (R/W) will be logic 1 (READ). Serial data is then
received from the slave on SDA while the SMBus outputs the serial clock. The slave transmits one or more
bytes of serial data.
The ACKRQ bit is set to 1 and an interrupt is generated after each received byte. Software must write the
ACK bit at that time to ACK or NACK the received byte.
Writing a 1 to the ACK bit generates an ACK; writing a 0 generates a NACK. Software should write a 0 to
the ACK bit for the last data transfer, to transmit a NACK. The interface exits Master Receiver Mode after
the STO bit is set and a STOP is generated. The interface will switch to Master Transmitter Mode if
SMB0DAT is written while an active Master Receiver. Figure 22.6 shows a typical master read sequence.
Two received data bytes are shown, though any number of bytes may be received. Notice that the ‘data
byte transferred’ interrupts occur before the ACK.
144
S
Received by SMBus
Interface
Transmitted by
SMBus Interface
SLA
Figure 22.6. Typical Master Read Sequence
R
A
Interrupt Locations
Data Byte
Rev 1.0
A
S = START
P = STOP
A = ACK
N = NACK
R = READ
SLA = Slave Address
Data Byte
N
P