C8051F321 Silicon Laboratories Inc, C8051F321 Datasheet - Page 189

• Manufacturer Part Number: C8051F321
• Description: IC 8051 MCU 16K FLASH 28MLP
• Manufacturer: Silicon Laboratories Inc
• Series: C8051F32xr

Specifications of C8051F321

• Core Processor: 8051
• Core Size: 8-Bit
• Speed: 25MHz
• Connectivity: SMBus (2-Wire/I²C), SPI, UART/USART, USB
• Peripherals: Brown-out Detect/Reset, POR, PWM, Temp Sensor, WDT
• Number Of I /o: 21
• Program Memory Size: 16KB (16K x 8)
• Program Memory Type: FLASH
• Ram Size: 2.25K x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 3.6 V
• Data Converters: A/D 13x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 28-VQFN Exposed Pad, 28-HVQFN, 28-SQFN, 28-DHVQFN
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Eeprom Size: -

16.5.3. Slave Receiver Mode
Serial data is received on SDA and the clock is received on SCL. When slave events are enabled (INH = 0), the inter-
face enters Slave Receiver Mode when a START followed by a slave address and direction bit (WRITE in this case)
is received. Upon entering Slave Receiver Mode, an interrupt is generated and the ACKRQ bit is set. Software
responds to the received slave address with an ACK, or ignores the received slave address with a NACK. If the
received slave address is ignored, 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. Software must write the ACK bit after each
received byte 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 16.10 shows a typical Slave Receiver 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 cycle in this mode.
S
Received by SMBus
Interface
Transmitted by
SMBus Interface
SLA
Figure 16.10. Typical Slave Receiver Sequence
Interrupt
W
A
Data Byte
Interrupt
Rev. 1.1
A
S = START
P = STOP
A = ACK
W = WRITE
SLA = Slave Address
Data Byte
Interrupt
A
Interrupt
C8051F320/1
P
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