ST STM32L4 5 Series User Manual

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RM0351 Inter-integrated circuit (I2C) interface
1301
DMA must be initialized before setting the START bit. The end of transfer is managed
with the NBYTES counter.
• In slave mode with NOSTRETCH=0, when all data are transferred using DMA, the
DMA must be initialized before the address match event, or in the ADDR interrupt
subroutine, before clearing the ADDR flag.
• If SMBus is supported (see Section 39.3: I2C implementation): the PEC transfer is
managed with the NBYTES counter. Refer to SMBus Slave receiver on page 1274 and
SMBus Master receiver on page 1278.
Note: If DMA is used for reception, the RXIE bit does not need to be enabled.
39.4.17 Debug mode
When the microcontroller enters debug mode (core halted), the SMBus timeout either
continues to work normally or stops, depending on the DBG_I2Cx_SMBUS_TIMEOUT
configuration bits in the DBG module.
39.5 I2C low-power modes
39.6 I2C interrupts
The table below gives the list of I2C interrupt requests.
Table 229. Effect of low-power modes on the I2C
Mode Description
Sleep No effect. I2C interrupts cause the device to exit the Sleep mode.
Low-power run No effect.
Low-power sleep No effect. I2C interrupts cause the device to exit the Low-power sleep mode.
Stop 0 / Stop 1
The I2C registers content is kept. If WUPEN = 1 and I2C is clocked by HSI16: the
address recognition is functional. The I2C address match condition causes the
device to exit the Stop 0 and Stop 1 modes. If WUPEN=0: the I2C must be
disabled before entering Stop mode.
Stop 2
The I2C registers content is kept. The I2C1, I2C2 and I2C4
(1)
must be disabled
before entering Stop 2. If WUPEN=1 and I2C3 is clocked by HSI16: the I2C3
address recognition is functional. The I2C3 address match condition causes the
device to exit the Stop mode 2. If WUPEN=0: the I2C3 must be disabled before
entering Stop 2 mode.
1. I2C4 not available on STM32L475xx/476xx/486xxdevices.
Standby
The I2C peripheral is powered down and must be reinitialized after exiting
Standby or Shutdown mode.
Shutdown

ST STM32L4 5 Series Specifications

General

Brand	ST
Model	STM32L4 5 Series
Category	Microcontrollers
Language	English