C8051T601-GMR Silicon Laboratories Inc, C8051T601-GMR Datasheet - Page 133

• Manufacturer Part Number: C8051T601-GMR
• Description: MCU 8-Bit C8051T60x 8051 CISC 8KB EPROM 1.8V/3V 14-Pin QFN EP T/R
• Manufacturer: Silicon Laboratories Inc

Specifications of C8051T601-GMR

• Package: 14QFN EP
• Device Core: 8051
• Family Name: C8051T60x
• Maximum Speed: 25 MHz
• Ram Size: 256 Byte
• Program Memory Size: 8 KB
• Operating Supply Voltage: 1.8|3 V
• Data Bus Width: 8 Bit
• Program Memory Type: EPROM
• Number Of Programmable I/os: 8
• Interface Type: I2C/SMBus/UART
• Operating Temperature: -40 to 85 °C
• Number Of Timers: 3

23.5.3. Write Sequence (Slave)
During a write sequence, an SMBus master writes data to a slave device. The slave in this transfer will be
a receiver during the address byte and a receiver during all data bytes. When slave events are enabled
(INH = 0), the interface enters Slave Receiver Mode when a START followed by a slave address and direc-
tion bit (WRITE in this case) is received. Upon entering Slave Receiver Mode, an interrupt is generated
and the ACKRQ bit is set. The software must respond to the received slave address with an ACK or ignore
the received slave address with a NACK.
If the received slave address is ignored by software (by NACKing the address), slave interrupts will be
inhibited until the next START is detected. If the received slave address is acknowledged, zero or more
data bytes are received.
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.
The interface exits Slave Receiver Mode after receiving a STOP. Note that the interface will switch to Slave
Transmitter Mode if SMB0DAT is written while an active Slave Receiver. Figure 23.7 shows a typical slave
write 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.
S
Received by SMBus
Interface
Transmitted by
SMBus Interface
SLA
Figure 23.7. Typical Slave Write Sequence
W
A
Data Byte
Rev. 1.2
Interrupt Locations
C8051T600/1/2/3/4/5/6
A
S = START
P = STOP
A = ACK
W = WRITE
SLA = Slave Address
Data Byte
A
P
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