GD32F10x User Manual
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Figure 17-5. SDA line arbitration
SDA
SCL
SDA from
master2
SDA from
master1
1
1
1
0
0
0
1
1
1
1
0
0
17.3.6.
I2C communication flow
Each I2C device is recognized by a unique address (whether it is a microcontroller, LCD driver,
memory or keyboard interface) and can be operated as either a transmitter or receiver,
depending on the function of the device.
An I2C slave will continue to detect addresses after a START signal on I2C bus and compare
the detected address with its slave address which is programmed by software. Once the two
addresses match with each other, the I2C slave will send an ACK to the I2C bus and respond
to the following command on I2C bus: transmitting or receiving the desired data. Additionally,
if General Call is enabled by software, the I2C slave always responds to a General Call
Address (0x00). The I2C block supports both 7-bit and 10-bit address modes.
An I2C master always initiates or ends a transfer using START or STOP signal and it’s also
responsible for SCL clock generation.
Figure 17-6. I2C communication flow with 7-bit address
Start
Slave address
W(0)
ACK
DATA0
ACK
DATAN
ACK
Stop
data transfer (N+1 bytes)
From master to slave
From slave to master
R(1)
DATA0
ACK
DATAN
NACK
Figure 17-7. I2C communication flow with 10-bit address (Master Transmit)
Start
Slave address byte2
W(0)
ACK
DATA0
ACK
DATAN
ACK
Stop
data transfer (N+1 bytes)
From master to slave
From slave to master
Slave address byte1
(header)
ACK
1 1 1 1 0 x x
Figure 17-8. I2C communication flow with 10-bit address (Master Receive)
Start
Slave address
byte2
W(0)
ACK
DATA0
ACK
DATAN
NACK
Stop
data transfer (N+1 bytes)
From master to slave
From slave to master
Slave address byte1
(header)
ACK
1 1 1 1 0 x x
ACK
Slave address
byte1 (header)
Start
R(1)
Summary of Contents for GD32F10 Series
Page 63: ...GD32F10x User Manual 63 programmed during the chip production ...
Page 117: ...GD32F10x User Manual 117 010 1 0 011 0 9 ...
Page 416: ...GD32F10x User Manual 416 shadow register updates every update event ...
Page 427: ...GD32F10x User Manual 427 value ...
Page 518: ...GD32F10x User Manual 518 These bits are not used in SPI mode ...