C8051F122 Silicon Laboratories Inc, C8051F122 Datasheet - Page 259

• Manufacturer Part Number: C8051F122
• Description: IC 8051 MCU FLASH 128K 100TQFP
• Manufacturer: Silicon Laboratories Inc
• Series: C8051F12xr

Specifications of C8051F122

• Core Processor: 8051
• Core Size: 8-Bit
• Speed: 100MHz
• Connectivity: EBI/EMI, SMBus (2-Wire/I²C), SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, POR, PWM, Temp Sensor, WDT
• Number Of I /o: 64
• Program Memory Size: 128KB (128K x 8)
• Program Memory Type: FLASH
• Ram Size: 8.25K x 8
• Voltage - Supply (vcc/vdd): 3 V ~ 3.6 V
• Data Converters: A/D 8x8b, 8x10b; D/A 2x12b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 100-TQFP, 100-VQFP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Eeprom Size: -

19. System Management Bus / I2C Bus (SMBus0)
The SMBus0 I/O interface is a two-wire, bi-directional serial bus. SMBus0 is compliant with the System
Management Bus Specification, version 1.1, and compatible with the I2C serial bus. Reads and writes to
the interface by the system controller are byte oriented with the SMBus0 interface autonomously control-
ling the serial transfer of the data. A method of extending the clock-low duration is available to accommo-
date devices with different speed capabilities on the same bus.
SMBus0 may operate as a master and/or slave, and may function on a bus with multiple masters. SMBus0
provides control of SDA (serial data), SCL (serial clock) generation and synchronization, arbitration logic,
and START/STOP control and generation.
SMBUS
IRQ
S
L
V
6
S
L
V
5
SMB0ADR
S
L
V
4
B
U
S
Y
Interrupt
Request
B
S
L
V
3
E
N
S
M
B
S
V
7
L
2
SMB0CN
S
T
A
A
S
L
V
1
O
S
T
S
L
V
0
S
I
G
C
A
A
F
T
E
B
O
T
E
SFR Bus
0000000b
SMBUS CONTROL LOGIC
Arbitration
SCL Synchronization
Status Generation
SCL Generation (Master Mode)
IRQ Generation
A
7 MSBs
S
T
A
7
Figure 19.1. SMBus0 Block Diagram
SFR Bus
S
T
A
6
SMB0STA
S
T
A
5
S
T
A
4
8
S
T
A
3
SMB0DAT
S
A
T
2
Read
S
T
A
1
7
S
T
A
0
6
8
SMB0DAT
5
4
C
R
7
3
C
R
6
Clock Divide
Data Path
8
Control
2
SMB0CR
C
R
5
Logic
1
SMB0DAT
Rev. 1.4
C
R
4
Write to
0
C
R
3
C
R
2
C
R
1
Control
C8051F120/1/2/3/4/5/6/7
C
R
0
SDA
Control
SCL
1
0
SYSCLK
FILTER
FILTER
C8051F130/1/2/3
N
N
SDA
SCL
C
R
O
S
S
B
A
R
Port I/O
259