ADP5586 Datasheet, PDF (18/44 Pages) Analog Devices – Keypad Decoder and I/O Port Expander

ADP5586
Data Sheet
Figure 27 shows a typical multibyte read sequence for reading
internal registers. The cycle begins with a start condition followed
by the 7-bit device address (0x34), followed by the R/W bit set
to 0 for a write cycle. The ADP5586 acknowledges the address
byte by pulling the data line low. The address of the register
from which data is to be read is sent next. The ADP5586 acknowl-
edges the register pointer byte by pulling the data line low. A start
condition is repeated, followed by the 7-bit device address (0x34),
followed by the R/W bit set to 1 for a read cycle. The ADP5586
acknowledges the address byte by pulling the data line low.
Next, the 8-bit data is then read. The address pointer is then
incremented to read the next data byte, and the host continues to
pull the data line low for each byte (master acknowledge) until
the n data byte is read. The host pulls the data line high (no
acknowledge) after the last byte is read, and a stop condition
completes the sequence.
START
0 = WRITE
REPEAT START
1 = READ
STOP
7-BIT DEVICE ADDRESS 0 0 8-BIT REGISTER POINTER 0
7-BIT DEVICE ADDRESS 1 0 READ BYTE 1 0 READ BYTE 2 0
0 READ BYTE n 1
ADP5586 ACK
ADP5586 ACK
ADP5586 ACK
MASTER ACK
Figure 27. I²C Multibyte Read Sequence
MASTER ACK MASTER ACK
NO ACK
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