ST STM32G471 User Manual

Inter-integrated circuit (I2C) interface RM0440
1912/2126 RM0440 Rev 4
41.7 I2C registers
Refer to Section 1.2 on page 72 for a list of abbreviations used in register descriptions.
The peripheral registers are accessed by words (32-bit).
41.7.1 I2C control register 1 (I2C_CR1)
Address offset: 0x00
Reset value: 0x0000 0000
Access: No wait states, except if a write access occurs while a write access to this register is
ongoing. In this case, wait states are inserted in the second write access until the previous
one is completed. The latency of the second write access can be up to
2xPCLK1+6xI2CCLK.
31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16
Res. Res. Res. Res. Res. Res. Res. Res. PECEN
ALERT
EN
SMBD
EN
SMBH
EN
GCEN
WUPE
N
NOSTR
ETCH
SBC
rw rw rw rw rw rw rw rw
15141312111098 7 6543210
RXDMA
EN
TXDMA
EN
Res.
ANF
OFF
DNF[3:0] ERRIE TCIE
STOP
IE
NACK
IE
ADDR
IE
RXIE TXIE PE
rw rw rw rw rw rw rw rw rw rw rw rw rw rw rw
Bits 31:24 Reserved, must be kept at reset value.
Bit 23 PECEN: PEC enable
0: PEC calculation disabled
1: PEC calculation enabled
Note: If the SMBus feature is not supported, this bit is reserved and forced by hardware to ‘0’.
Refer to Section 41.3: I2C implementation.
Bit 22 ALERTEN: SMBus alert enable
0: The SMBus alert pin (SMBA) is not supported in host mode (SMBHEN=1). In device mode
(SMBHEN=0), the SMBA pin is released and the Alert Response Address header is disabled
(0001100x followed by NACK).
1: The SMBus alert pin is supported in host mode (SMBHEN=1). In device mode
(SMBHEN=0), the SMBA pin is driven low and the Alert Response Address header is
enabled (0001100x followed by ACK).
Note: When ALERTEN=0, the SMBA pin can be used as a standard GPIO.
If the SMBus feature is not supported, this bit is reserved and forced by hardware to ‘0’.
Refer to Section 41.3: I2C implementation.
Bit 21 SMBDEN: SMBus Device Default Address enable
0: Device Default Address disabled. Address 0b1100001x is NACKed.
1: Device Default Address enabled. Address 0b1100001x is ACKed.
Note: If the SMBus feature is not supported, this bit is reserved and forced by hardware to ‘0’.
Refer to Section 41.3: I2C implementation.
Bit 20 SMBHEN: SMBus Host Address enable
0: Host Address disabled. Address 0b0001000x is NACKed.
1: Host Address enabled. Address 0b0001000x is ACKed.
Note: If the SMBus feature is not supported, this bit is reserved and forced by hardware to ‘0’.
Refer to Section 41.3: I2C implementation.

ST STM32G471 Specifications

General

Brand	ST
Model	STM32G471
Category	Microcontrollers
Language	English