GD32A50x User Manual
509
Figure 20-1. I2C module block diagram
Receive
Data
Register
A
P
B
B
u
s
SDA Controller
CRC Calculation /
Check
PEC register
SCL Controller
Timing and
Control Logic
Control Registers
Status Flags
DMA/ Interrupts
SMBA
Analog
Noise
filter
Digital
Noise
filter
Analog
Noise
filter
Digital
Noise
filter
Transmit
Data
Register
Shift
Register
SDA
SCL
Table 20-1. Definition of I2C-bus terminology (refer to the I2C specification of Philips
semiconductors)
Term
Description
Transmitter
the device which sends data to the bus
Receiver
the device which receives data from the bus
Master
the device which initiates a transfer, generates clock signals and terminates a
transfer
Slave
the device addressed by a master
Multi-master
more than one master can attempt to control the bus at the same time without
corrupting the message
Arbitration
procedure to ensure that, if more than one master tries to control the bus
simultaneously, only one is allowed to do so and the winning master’s
message is not corrupted
20.3.1.
Clock requirements
The I2CCLK period t
I2CCLK
must match the conditions as follows:
t
I2CCLK
<
(
t
LOW
-t
filters
)
/4
t
I2CCLK
<t
HIGH
with:
t
LOW
: SCL low time
t
HIGH
: SCL high time
t
filters
: When the filters are enabled, represent the delays by the analog filter and digital filter.