C8051F332-GM Silicon Laboratories Inc, C8051F332-GM Datasheet - Page 142

• Manufacturer Part Number: C8051F332-GM
• Description: IC 8051 MCU 4KB FLASH 20QFN
• Manufacturer: Silicon Laboratories Inc
• Series: C8051F33xr

Specifications of C8051F332-GM

• Program Memory Type: FLASH
• Program Memory Size: 4KB (4K x 8)
• Package / Case: 20-QFN
• Core Processor: 8051
• Core Size: 8-Bit
• Speed: 25MHz
• Connectivity: SMBus (2-Wire/I²C), SPI, UART/USART
• Peripherals: POR, PWM, Temp Sensor, WDT
• Number Of I /o: 17
• Ram Size: 768 x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 3.6 V
• Data Converters: A/D 16x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Processor Series: C8051F3x
• Core: 8051
• Data Bus Width: 8 bit
• Data Ram Size: 768 B
• Interface Type: I2C/SMBus/SPI/UART
• Maximum Clock Frequency: 25 MHz
• Number Of Programmable I/os: 17
• Number Of Timers: 4
• Operating Supply Voltage: 2.7 V to 3.6 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• 3rd Party Development Tools: KSK-SL-TOOLSTICK, PK51, CA51, A51, ULINK2
• Development Tools By Supplier: C8051F330DK
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 16-ch x 10-bit
• No. Of I/o's: 17
• Ram Memory Size: 768Byte
• Cpu Speed: 25MHz
• No. Of Timers: 4
• Rohs Compliant: Yes
• Package: 20QFN
• Device Core: 8051
• Family Name: C8051F33x
• Maximum Speed: 25 MHz
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With: 770-1006 - ISP 4PORT FOR SILABS C8051F MCU336-1451 - ADAPTER PROGRAM TOOLSTICK F330
• Eeprom Size: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• Other names: 336-1266

C8051F330/1/2/3/4/5
15.4.3. Data Register
The SMBus Data register SMB0DAT holds a byte of serial data to be transmitted or one that has just been
received. Software may safely read or write to the data register when the SI flag is set. Software should not
attempt to access the SMB0DAT register when the SMBus is enabled and the SI flag is cleared to logic 0,
as the interface may be in the process of shifting a byte of data into or out of the register.
Data in SMB0DAT is always shifted out MSB first. After a byte has been received, the first bit of received
data is located at the MSB of SMB0DAT. While data is being shifted out, data on the bus is simultaneously
being shifted in. SMB0DAT always contains the last data byte present on the bus. In the event of lost arbi-
tration, the transition from master transmitter to slave receiver is made with the correct data or address in
SMB0DAT.
15.5. SMBus Transfer Modes
The SMBus interface may be configured to operate as master and/or slave. At any particular time, it will be
operating in one of the following four modes: Master Transmitter, Master Receiver, Slave Transmitter, or
Slave Receiver. The SMBus interface enters Master Mode any time a START is generated, and remains in
Master Mode until it loses an arbitration or generates a STOP. An SMBus interrupt is generated at the end
of all SMBus byte frames; however, note that the interrupt is generated before the ACK cycle when operat-
ing as a receiver, and after the ACK cycle when operating as a transmitter.
15.5.1. Master Transmitter Mode
Serial data is transmitted on SDA while the serial clock is output on SCL. The SMBus interface generates
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 0 (WRITE). The master then transmits
one or more bytes of serial data. After each byte is transmitted, an acknowledge bit is generated by the
slave. The transfer is ended when the STO bit is set and a STOP is generated. Note that the interface will
switch to Master Receiver Mode if SMB0DAT is not written following a Master Transmitter interrupt.
Figure 15.5 shows a typical Master Transmitter sequence. Two transmit data bytes are shown, though any
number of bytes may be transmitted. Notice that the ‘data byte transferred’ interrupts occur after the ACK
cycle in this mode.
146
Bits7–0: SMB0DAT: SMBus Data.
R/W
Bit7
The SMB0DAT register contains a byte of data to be transmitted on the SMBus serial inter-
face or a byte that has just been received on the SMBus serial interface. The CPU can read
from or write to this register whenever the SI serial interrupt flag (SMB0CN.0) is set to
logic 1. The serial data in the register remains stable as long as the SI flag is set. When the
SI flag is not set, the system may be in the process of shifting data in/out and the CPU
should not attempt to access this register.
R/W
Bit6
SFR Definition 15.3. SMB0DAT: SMBus Data
R/W
Bit5
R/W
Bit4
Rev. 1.7
R/W
Bit3
R/W
Bit2
R/W
Bit1
SFR Address:
R/W
Bit0
0xC2
00000000
Reset Value