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Field
Name
R/W
Description
11
ACKPOS
R/W
Acknowledge /PEC Position Configure
This bit can be set to 1 or cleared by software; when I2CEN=0, it
is cleared by hardware.
0: When receiving current byte, whether transmitting NACK/ACK,
whether PEC is in shift register
1: When receiving next byte, whether transmitting NACK/ACK and
whether PEC is in the next byte of shift register
12
PEC
R/W
Packet Error Check Transfer Enable
This bit can be set to 1 or 0 by software; after PEC, start bit or
stop bit is transmitted, or when I2CEN=0, it is set to 0 by
hardware.
0: Disable
1: Enable
13
ALERTEN
R/W
SMBus Alert Enable
This bit can be set to 1 or cleared by software; when I2CEN=0, it
is cleared by software.
0: Release the SMBAlert pin to make it higher, and remind to
transmit the response address header immediately after
transmitting the NACK signal
1: Drive SMBAlert pin to make it lower, and remind to transmit the
response address header immediately after transmitting the
ACKEN signal
14
Reserved
15
SWRST
R/W
Software Configure I2C under Reset State
0: Not reset
1: Reset; before I2C reset, ensure that I2C pin is released and the
bus is in idle state.
Control register 2 (I2C_CTRL2)
Offset address: 0x04
Reset value: 0x0000
Field
Name
R/W
Description
5:0
CLKFCFG R/W
I2C Clock Frequency Configure
The clock frequency is the clock of I2C module, namely, the clock input
from APB bus.
0: Disable
1: Disable
2
:
2MHz
...
50
:
50MHz
Greater than 100100: Disable.
Minimum clock frequency of I2C bus: the standard mode is 1MHz, and
the fast mode is 4MHz.
7:6
Reserved