C8051F020-TB Silicon Laboratories Inc, C8051F020-TB Datasheet - Page 203

• Manufacturer Part Number: C8051F020-TB
• Description: BOARD PROTOTYPING W/C8051F020
• Manufacturer: Silicon Laboratories Inc
• Type: MCUr

Specifications of C8051F020-TB

• Contents: Board
• Processor To Be Evaluated: C8051F02x
• Interface Type: USB
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• For Use With/related Products: C8051F020
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

Bits7-0:
Bits7-0:
SCR7
R/W
R/W
Bit7
Bit7
SCR7-SCR0: SPI0 Clock Rate
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 down version of the system clock, and is
given in the following equation, where SYSCLK is the system clock frequency and SPI0CR is the 8-
bit value held in the SPI0CR register.
f
for 0 <= SPI0CKR <= 255
Example: If SYSCLK = 2 MHz and SPI0CKR = 0x04,
f
f
SPI0DAT: SPI0 Transmit and Receive Data.
The SPI0DAT register is used to transmit and receive SPI0 data. Writing data to SPI0DAT places the
data immediately into the shift register and initiates a transfer when in Master Mode. A read of
SPI0DAT returns the contents of the receive buffer.
SCK
SCK
SCK
SCR6
R/W
R/W
Bit6
Bit6
=
=
=
------------------------------------------------ -
2
------------------------- -
2
200kHz
2000000


Figure 19.7. SPI0CKR: SPI0 Clock Rate Register


SPI0CKR
4
SYSCLK
SCR5
Figure 19.8. SPI0DAT: SPI0 Data Register
R/W
R/W
Bit5
+
Bit5
1

+
SCR4
R/W
R/W
Bit4
Bit4
1

SCR3
R/W
R/W
Bit3
Bit3
Rev. 1.4
SCR2
R/W
R/W
Bit2
Bit2
SCR1
C8051F020/1/2/3
R/W
R/W
Bit1
Bit1
SCR0
R/W
R/W
Bit0
Bit0
SFR Address:
SFR Address:
00000000
00000000
Reset Value
Reset Value
0x9D
0x9B
203