C8051F331 Silicon Laboratories Inc, C8051F331 Datasheet - Page 157

• Manufacturer Part Number: C8051F331
• Description: IC 8051 MCU 8K FLASH 20MLP
• Manufacturer: Silicon Laboratories Inc
• Series: C8051F33xr

Specifications of C8051F331

• Core Processor: 8051
• Core Size: 8-Bit
• Speed: 25MHz
• Connectivity: SMBus (2-Wire/I²C), SPI, UART/USART
• Peripherals: POR, PWM, WDT
• Number Of I /o: 17
• Program Memory Size: 8KB (8K x 8)
• Program Memory Type: FLASH
• Ram Size: 768 x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 3.6 V
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 20-QFN
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Eeprom Size: -
• Data Converters: -

17.
The Enhanced Serial Peripheral Interface (SPI0) provides access to a flexible, full-duplex synchronous
serial bus. SPI0 can operate as a master or slave device in both 3-wire or 4-wire modes, and supports mul-
tiple masters and slaves on a single SPI bus. The slave-select (NSS) signal can be configured as an input
to select SPI0 in slave mode, or to disable Master Mode operation in a multi-master environment, avoiding
contention on the SPI bus when more than one master attempts simultaneous data transfers. NSS can
also be configured as a chip-select output in master mode, or disabled for 3-wire operation. Additional gen-
eral purpose port I/O pins can be used to select multiple slave devices in master mode.
Enhanced Serial Peripheral Interface (SPI0)
SYSCLK
Clock Divide
SPI0CKR
SFR Bus
SPI0DAT
Logic
Write
Transmit Data Buffer
Receive Data Buffer
7
6
Shift Register
Figure 17.1. SPI Block Diagram
5
SPI CONTROL LOGIC
4
3
Data Path
2
SFR Bus
Control
SPI0CFG
SPI0DAT
1
SPI0DAT
Read
0
C8051F330/1, C8051F330D
Rev. 1.2
Tx Data
Rx Data
Pin Interface
Control
Control
Logic
Pin
SPI0CN
MOSI
MISO
SCK
NSS
O
C
R
S
S
B
A
R
SPI IRQ
Port I/O
157