C8051F312 Silicon Laboratories Inc, C8051F312 Datasheet - Page 182

• Manufacturer Part Number: C8051F312
• Description: IC 8051 MCU 8K FLASH 32LQFP
• Manufacturer: Silicon Laboratories Inc
• Series: C8051F31xr

Specifications of C8051F312

• 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: 29
• Program Memory Size: 8KB (8K x 8)
• Program Memory Type: FLASH
• Ram Size: 1.25K x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 3.6 V
• Data Converters: A/D 21x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 32-LQFP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Eeprom Size: -
• Other names: 336-1151

C8051F310/1/2/3/4/5/6/7
182
Bits 7–0: SPI0DAT: SPI0 Transmit and Receive Data.
Bits 7–0: SCR7–SCR0: SPI0 Clock Rate.
Example: If SYSCLK = 2 MHz and SPI0CKR = 0x04,
f
SCK
SCR7
f
R/W
Bit7
SCK
R/W
Bit7
=
=
The SPI0DAT register is used to transmit and receive SPI0 data. Writing data to SPI0DAT
places the data into the transmit buffer and initiates a transfer when in Master Mode. A read
of SPI0DAT returns the contents of the receive buffer.
These bits determine the frequency of the SCK output when the SPI0 module is configured
for master mode operation. The SCK clock frequency is a divided version of the system
clock, and is given in the following equation, where SYSCLK is the system clock frequency
and SPI0CKR is the 8-bit value held in the SPI0CKR register.
for 0 <= SPI0CKR <= 255
200kHz
f
SCK
------------------------- -
2
2000000
SCR6

R/W
Bit6
R/W
Bit6

=
4
+
------------------------------------------------ -
2
SFR Definition 16.3. SPI0CKR: SPI0 Clock Rate

1


SFR Definition 16.4. SPI0DAT: SPI0 Data
SPI0CKR
SCR5
SYSCLK
R/W
Bit5
R/W
Bit5
SCR4
+
R/W
Bit4
R/W
Bit4
1

Rev. 1.7
SCR3
R/W
Bit3
R/W
Bit3
SCR2
R/W
Bit2
R/W
Bit2
SCR1
R/W
Bit1
R/W
Bit1
SFR Address: 0xA3
SFR Address: 0xA2
SCR0
R/W
Bit0
R/W
Bit0
00000000
Reset Value
00000000
Reset Value