CAP1214 Datasheet, PDF (20/107 Pages) SMSC Corporation – Multiple Channel Capacitive Touch Sensor and LED Driver

Multiple Channel Capacitive Touch Sensor and LED Driver
Datasheet
4.2.1 SMBus Write Byte
The Write Byte is used to write one byte of data to a specific register as shown in Table 4.2.
CLIENT
START ADDRESS
WR
1 ->0
0101_000
0
Table 4.2 Write Byte Protocol
ACK
0
REGISTER
ADDRESS
XXh
ACK
0
REGISTER
DATA
XXh
ACK
0
STOP
0 -> 1
4.2.2 Block Write
The Block Write is used to write multiple data bytes to a group of contiguous registers as shown in
Table 4.3. It is an extension of the Write Byte Protocol.
APPLICATION NOTE: When using the Block Write protocol, the internal address pointer will be automatically
incremented after every data byte is received. It will wrap from FFh to 00h.
START
1 ->0
REGISTER
DATA
XXh
CLIENT
ADDRESS
0101_000
ACK
0
Table 4.3 Block Write Protocol
WR
0
REGISTER
DATA
XXh
ACK
0
ACK
0
REGISTER
ADDRESS
XXh
...
...
ACK
0
REGISTER
DATA
XXh
REGISTER
DATA
XXh
ACK
0
ACK
0
STOP
0 -> 1
4.2.3
SMBus Read Byte
The Read Byte protocol is used to read one byte of data from the registers as shown in Table 4.4.
Table 4.4 Read Byte Protocol
START
CLIENT
WR ACK REGISTER ACK START
CLIENT
RD
ADDRESS
ADDRESS
ADDRESS
1->0 0101_000 0 0
XXh
0
1 ->0 0101_000 1
ACK
0
REGISTER
DATA
XXh
NACK STOP
1
0 -> 1
4.2.4 Block Read
The Block Read is used to read multiple data bytes from a group of contiguous registers as shown in
Table 4.5. It is an extension of the Read Byte Protocol.
APPLICATION NOTE: When using the Block Read protocol, the internal address pointer will be automatically
incremented after every data byte is received. It will wrap from FFh to 00h.
Revision 1.0 (08-30-10)
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