C8051F320DK Silicon Laboratories Inc, C8051F320DK Datasheet - Page 169

• Manufacturer Part Number: C8051F320DK
• Description: DEV KIT FOR C8051F320/F321
• Manufacturer: Silicon Laboratories Inc
• Type: MCUr

Specifications of C8051F320DK

• Contents: Evaluation Board, Power Supply, USB Cables, Adapter and Documentation
• Processor To Be Evaluated: C8051F320/F321
• Interface Type: USB
• Silicon Manufacturer: Silicon Labs
• Core Architecture: 8051
• Silicon Core Number: C8051F320
• Silicon Family Name: C8051F32x
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• For Use With/related Products: Silicon Laboratories C8051F320, C8051F321
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• Other names: 336-1260

16. SMBus
The SMBus I/O interface is a two-wire, bi-directional serial bus. The SMBus is compliant with the System
Management Bus Specification, version 1.1, and compatible with the I
the interface by the system controller are byte oriented with the SMBus interface autonomously controlling
the serial transfer of the data. Data can be transferred at up to 1/20th of the system clock as a master or
slave (this can be faster than allowed by the SMBus specification, depending on the system clock used). A
method of extending the clock-low duration is available to accommodate devices with different speed
capabilities on the same bus.
The SMBus interface may operate as a master and/or slave, and may function on a bus with multiple mas-
ters. The SMBus provides control of SDA (serial data), SCL (serial clock) generation and synchronization,
arbitration logic, and START/STOP control and generation. Three SFRs are associated with the SMBus:
SMB0CF configures the SMBus; SMB0CN controls the status of the SMBus; and SMB0DAT is the data
register, used for both transmitting and receiving SMBus data and slave addresses.
M
A
S
E
R
T
Interrupt
Request
M
O
D
T
X
E
SMB0CN
S
T
A
O
S
T
Q
A
C
K
R
O
A
R
B
S
L
T
A
C
K
S
I
Arbitration
SCL Synchronization
SCL Generation (Master Mode)
SDA Control
IRQ Generation
SMBUS CONTROL LOGIC
E
N
S
M
B
N
H
Figure 16.1. SMBus Block Diagram
I
U
SMB0CF
B
S
Y
O
E
X
T
H
L
D
M
O
S
B
T
E
7
M
S
B
F
T
E
6
SMB0DAT
M
S
B
C
S
1
5
S
M
B
C
S
0
4
Data Path
3
Control
2
1
0
Rev. 1.4
00
01
10
11
Control
Control
SDA
SCL
T0 Overflow
T1 Overflow
TMR2H Overflow
TMR2L Overflow
FILTER
FILTER
2
N
N
C serial bus. Reads and writes to
SDA
SCL
C8051F320/1
C
R
O
S
S
B
A
R
Port I/O
169