C8051F331 Silicon Laboratories Inc, C8051F331 Datasheet - Page 164
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C8051F331
Manufacturer Part Number
C8051F331
Description
IC 8051 MCU 8K FLASH 20MLP
Manufacturer
Silicon Laboratories Inc
Series
C8051F33xr
Datasheet
1.C8051F330R.pdf
(208 pages)
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
-
Available stocks
Company
Part Number
Manufacturer
Quantity
Price
Part Number:
C8051F331
Manufacturer:
SILICON LABS/芯科
Quantity:
20 000
Company:
Part Number:
C8051F331-GM
Manufacturer:
SiliconL
Quantity:
1 630
Part Number:
C8051F331-GM
Manufacturer:
SILICON LABS/芯科
Quantity:
20 000
Part Number:
C8051F331-GMR
Manufacturer:
SILICON LABS/芯科
Quantity:
20 000
C8051F330/1, C8051F330D
17.6. SPI Special Function Registers
SPI0 is accessed and controlled through four special function registers in the system controller: SPI0CN
Control Register, SPI0DAT Data Register, SPI0CFG Configuration Register, and SPI0CKR Clock Rate
Register. The four special function registers related to the operation of the SPI0 Bus are described in the
following figures.
*Note: In slave mode, data on MOSI is sampled in the center of each data bit. In master mode, data on MISO is
164
Bit 7:
Bit 6:
Bit 5:
Bit 4:
Bit 3:
Bit 2:
Bit 1:
Bit 0:
SPIBSY
Bit7
sampled one SYSCLK before the end of each data bit, to provide maximum settling time for the slave device.
See Table 17.1 for timing parameters.
R
SPIBSY: SPI Busy (read only).
This bit is set to logic 1 when a SPI transfer is in progress (Master or slave Mode).
MSTEN: Master Mode Enable.
0: Disable master mode. Operate in slave mode.
1: Enable master mode. Operate as a master.
CKPHA: SPI0 Clock Phase.
This bit controls the SPI0 clock phase.
0: Data centered on first edge of SCK period.
1: Data centered on second edge of SCK period.
CKPOL: SPI0 Clock Polarity.
This bit controls the SPI0 clock polarity.
0: SCK line low in idle state.
1: SCK line high in idle state.
SLVSEL: Slave Selected Flag (read only).
This bit is set to logic 1 whenever the NSS pin is low indicating SPI0 is the selected slave. It
is cleared to logic 0 when NSS is high (slave not selected). This bit does not indicate the
instantaneous value at the NSS pin, but rather a de-glitched version of the pin input.
NSSIN: NSS Instantaneous Pin Input (read only).
This bit mimics the instantaneous value that is present on the NSS port pin at the time that
the register is read. This input is not de-glitched.
SRMT: Shift Register Empty (Valid in Slave Mode, read only).
This bit will be set to logic 1 when all data has been transferred in/out of the shift register,
and there is no new information available to read from the transmit buffer or write to the
receive buffer. It returns to logic 0 when a data byte is transferred to the shift register from
the transmit buffer or by a transition on SCK.
NOTE: SRMT = 1 when in Master Mode.
RXBMT: Receive Buffer Empty (Valid in Slave Mode, read only).
This bit will be set to logic 1 when the receive buffer has been read and contains no new
information. If there is new information available in the receive buffer that has not been read,
this bit will return to logic 0.
NOTE: RXBMT = 1 when in Master Mode.
MSTEN
R/W
Bit6
Figure 17.8. SPI0CFG: SPI0 Configuration Register
CKPHA
R/W
Bit5
CKPOL
R/W
Bit4
SLVSEL
Rev. 1.2
Bit3
R
*
NSSIN
*
Bit2
R
SRMT
Bit1
R
SFR Address: 0xA1
RXBMT
Bit0
R
Reset Value
00000111