STUSB1602 Datasheet, PDF (24/55 Pages) STMicroelectronics – Power hubs and docking stations

I²C interface
5
I²C interface
STUSB1602
5.1
Read and write operations
The I²C interface is used to configure, control and read the operation status of the device. It
is compatible with the Philips I²C Bus® (version 2.1). The I²C is a slave serial interface
based on two signals:
• SCL - Serial clock line: input clock used to shift data
• SDA - Serial data line: input/output bidirectional data transfers
A filter rejects the potential spikes on the bus data line to preserve data integrity.
The bidirectional data line supports transfers up to 400 Kbit/s (fast mode). The data are
shifted to and from the chip on the SDA line, MSB first.
The first bit must be high (START) followed by the 7-bit device address and the read/write
control bit.
Two 7-bit device addresses are available for the STUSB1602 thanks to external
programming of DevADDR0 through ADDR0 pin setting, i.e. 0x28 or 0x29. This allows two
STUSB1602 devices to be connected on the same I²C bus.
Table 11. Device address format
Bit7
Bit6
Bit5
Bit4
Bit3
Bit2
Bit1
Bit0
DevADDR6 DevADDR5 DevADDR4 DevADDR3 DevADDR2 DevADDR1 DevADDR0 R/W
0
1
0
1
0
0
ADDR0 0/1
Table 12. Register address format
Bit7
Bit6
Bit5
Bit4
Bit3
Bit2
Bit1
Bit0
RegADDR7 RegADDR6 RegADDR5 RegADDR4 RegADDR3 RegADDR2 RegADDR1 RegADDR0
Bit7
DATA7
Bit6
DATA6
Table 13. Register data format
Bit5
Bit4
Bit3
Bit2
DATA5
DATA4
DATA3
DATA2
Bit1
DATA1
Bit0
DATA0
Figure 5. Read operation
DĂƐƚĞƌ
^ůĂǀĞ
^ƚĂƌƚ ĞǀŝĐĞ ĂĚĚƌ t  ZĞŐ ĂĚĚƌĞƐƐ  ZĞƐƚĂƌƚ ĞǀŝĐĞ ĂĚĚƌ Z  ZĞŐ ĚĂƚĂ  ZĞŐ ĚĂƚĂ  ZĞŐ ĚĂƚĂ _ ^ƚŽƉ
ϳ ďŝƚƐ
ϴ ďŝƚƐ
ϳ ďŝƚƐ
ϴ ďŝƚƐ
ϴ ďŝƚƐ
ϴ ďŝƚƐ
^ƚĂƌƚďŝƚ с ^ ĨĂůůŝŶŐ ǁŚĞŶ ^> с ϭ
^ƚŽƉ ďŝƚ с ^ ƌŝƐŝŶŐ ǁŚĞŶ ^> с ϭ
ZĞƐƚĂƌƚďŝƚ с ƐƚĂƌƚ ĂĨƚĞƌĂ ƐƚĂƌƚ
ĐŬŶŽǁůĞĚŐ Ğ с ^ ĨŽƌĐĞĚ ůŽǁ ĚƵƌŝŶŐ Ă^> ĐůŽĐŬ
ĚĚƌĞƐƐ
Ŷнϭ
ĚĚƌĞƐƐ
ŶнϮ
24/55
DocID028319 Rev 2