ST7232AK2-Auto STMicroelectronics, ST7232AK2-Auto Datasheet - Page 106

• Manufacturer Part Number: ST7232AK2-Auto
• Description: 8-bit MCU for automotive, 16 Kbyte Flash, 10-bit ADC, 4 timers, SPI, SCI
• Manufacturer: STMicroelectronics

Specifications of ST7232AK2-Auto

• Hdflash Endurance: 100 cycles, data retention
• Clock Sources: crystal/ceramic resonator oscillators and bypass for external clock
• Four Power Saving Modes: halt, active halt, wait and slow
• Main Clock Controller With: real time base, beep and clock-out capabilities
• Two 16-bit Timers With: 2 input captures, 2 output compares, PWM and pulse generator modes

On-chip peripherals
Note:
Note:
106/201
1
2
Figure 48. Generic SS timing diagram
Figure 49. Hardware/software slave select management
Master mode operation
In master mode, the serial clock is output on the SCK pin. The clock frequency, polarity and
phase are configured by software (refer to the description of the SPICSR register).
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).
To operate the SPI in master mode, perform the following steps in order:
1.
2.
3.
If the SPICSR register is not written first, the SPICR register setting (MSTR bit) may be not
taken into account.
MSTR and SPE bits remain set only if SS is high).
The transmit sequence begins when software writes a byte in the SPIDR register.
Write to the SPICR register:
–
–
Write to the SPICSR register:
–
Write to the SPICR register:
–
MOSI/MISO
Master SS
if CPHA = 0
if CPHA = 1
Slave SS
Slave SS
Select the clock frequency by configuring the SPR[2:0] bits
Select the clock polarity and clock phase by configuring the CPOL and CPHA bits.
Figure 50
Note: The slave must have the same CPOL and CPHA settings as the master.
Either set the SSM bit and set the SSI bit or clear the SSM bit and tie the SS pin
high for the complete byte transmit sequence.
Set the MSTR and SPE bits
shows the four possible configurations.
SS external pin
SSI bit
Byte 1
SSM bit
1
0
Byte 2
SS internal
Byte 3
ST7232Axx-Auto