STEVAL-ISQ002V1 STMicroelectronics, STEVAL-ISQ002V1 Datasheet - Page 80

• Manufacturer Part Number: STEVAL-ISQ002V1
• Description: BOARD EVAL BASED ON ST72264G1
• Manufacturer: STMicroelectronics

Specifications of STEVAL-ISQ002V1

• Main Purpose: Interface, PMBus
• Embedded: Yes, MCU, 8-Bit
• Utilized Ic / Part: ST72F264
• Primary Attributes: The PMBus™ Interface Using the ST7 I2C Peripheral
• Secondary Attributes: Firmware in C Language
• Product: Power Management Modules
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 497-6423

ST72260Gx, ST72262Gx, ST72264Gx
SERIAL PERIPHERAL INTERFACE (Cont’d)
11.4.4 Clock Phase and Clock Polarity
Four possible timing relationships may be chosen
by software, using the CPOL and CPHA bits (See
Figure
Note: The idle state of SCK must correspond to
the polarity selected in the SPICSR register (by
pulling up SCK if CPOL=1 or pulling down SCK if
CPOL=0).
The combination of the CPOL clock polarity and
CPHA (clock phase) bits selects the data capture
clock edge
Figure 50. Data Clock Timing Diagram
80/172
(from slave)
(from slave)
50).
(to slave)
(to slave)
(from master)
(from master)
MISO
MOSI
CAPTURE STROBE
SCK
(CPOL = 1)
SCK
(CPOL = 0)
MISO
MOSI
SS
CAPTURE STROBE
SCK
(CPOL = 1)
SCK
(CPOL = 0)
SS
Note: This figure should not be used as a replacement for parametric information.
Refer to the Electrical Characteristics chapter.
MSBit
MSBit
MSBit
MSBit
Bit 6
Bit 6
Bit 6
Bit 6
Bit 5
Bit 5
Bit 5
Bit 5
CPHA =0
CPHA =1
Bit 4
Bit 4
Bit 4
Bit 4
Figure
combinations of the CPHA and CPOL bits. The di-
agram may be interpreted as a master or slave
timing diagram where the SCK pin, the MISO pin,
the MOSI pin are directly connected between the
master and the slave device.
Note: If CPOL is changed at the communication
byte boundaries, the SPI must be disabled by re-
setting the SPE bit.
Bit3
Bit3
Bit3
Bit3
50, shows an SPI transfer with the four
Bit 2
Bit 2
Bit 2
Bit 2
Bit 1
Bit 1
Bit 1
Bit 1
LSBit
LSBit
LSBit
LSBit