C8051F310-GQ Silicon Laboratories Inc, C8051F310-GQ Datasheet - Page 168

• Manufacturer Part Number: C8051F310-GQ
• Description: IC 8051 MCU 16K FLASH 32LQFP
• Manufacturer: Silicon Laboratories Inc
• Series: C8051F31xr

Specifications of C8051F310-GQ

• Core Size: 8-Bit
• Program Memory Size: 16KB (16K x 8)
• Oscillator Type: Internal
• Core Processor: 8051
• Speed: 25MHz
• Connectivity: SMBus (2-Wire/I²C), SPI, UART/USART
• Peripherals: POR, PWM, Temp Sensor, WDT
• Number Of I /o: 29
• 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
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 32-LQFP
• No. Of I/o's: 29
• Ram Memory Size: 1280Byte
• Cpu Speed: 25MHz
• No. Of Timers: 4
• No. Of Pwm Channels: 5
• Digital Ic Case: RoHS Compliant
• Rohs Compliant: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With: 770-1006 - ISP 4PORT FOR SILABS C8051F MCU336-1445 - ADAPTER PROGRAM TOOLSTICK F310336-1329 - KIT REF DESIGN SENSORLESS BLDC336-1253 - DEV KIT FOR C8051F310/F311
• Eeprom Size: -
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 336-1252

C8051F310/1/2/3/4/5
16.5. Serial Clock Timing
Four combinations of serial clock phase and polarity can be selected using the clock control bits in the
SPI0 Configuration Register (SPI0CFG). The CKPHA bit (SPI0CFG.5) selects one of two clock phases
(edge used to latch the data). The CKPOL bit (SPI0CFG.4) selects between an active-high or active-low
clock. Both master and slave devices must be configured to use the same clock phase and polarity. SPI0
should be disabled (by clearing the SPIEN bit, SPI0CN.0) when changing the clock phase or polarity. The
clock and data line relationships for master mode are shown in Figure 16.5. For slave mode, the clock and
data relationships are shown in Figure 16.6 and Figure 16.7. CKPHA must be set to ‘0’ on both the master
and slave SPI when communicating between two of the following devices: C8051F04x, C8051F06x,
C8051F12x, C8051F31x, C8051F32x, and C8051F33x
The SPI0 Clock Rate Register (SPI0CKR) as shown in SFR Definition 16.3 controls the master mode
serial clock frequency. This register is ignored when operating in slave mode. When the SPI is configured
as a master, the maximum data transfer rate (bits/sec) is one-half the system clock frequency or 12.5 MHz,
whichever is slower. When the SPI is configured as a slave, the maximum data transfer rate (bits/sec) for
full-duplex operation is 1/10 the system clock frequency, provided that the master issues SCK, NSS (in 4-
wire slave mode), and the serial input data synchronously with the slave’s system clock. If the master
issues SCK, NSS, and the serial input data asynchronously, the maximum data transfer rate (bits/sec)
must be less than 1/10 the system clock frequency. In the special case where the master only wants to
transmit data to the slave and does not need to receive data from the slave (i.e. half-duplex operation), the
SPI slave can receive data at a maximum data transfer rate (bits/sec) of 1/4 the system clock frequency.
This is provided that the master issues SCK, NSS, and the serial input data synchronously with the slave’s
system clock.
168
NSS (Must Remain High
in Multi-Master Mode)
SCK
(CKPOL=0, CKPHA=0)
SCK
(CKPOL=0, CKPHA=1)
SCK
(CKPOL=1, CKPHA=0)
SCK
(CKPOL=1, CKPHA=1)
MISO/MOSI
Figure 16.5. Master Mode Data/Clock Timing
MSB
Bit 6
Bit 5
Rev. 1.5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0