SX8650 Datasheet, PDF (32/56 Pages) Semtech Corporation – World’s Lowest Power & Smallest Footprint 4-wire Resistive Touchscreen Controller with 15kV ESD

SX8650
World’s Lowest Power & Smallest Footprint 4-wire
Resistive Touchscreen Controller with 15kV ESD
ADVANCED COMMUNICATIONS & SENSING
DATASHEET
4.6.4. I2C Host Commands
The format for I2C commands is given in Figure 30.
After the start condition [S], the SX8650 Slave Address (SA) is sent, followed by an eighth bit (W=‘0’) indicating a Write.
The SX8650 then Acknowledges [A] that it is being addressed, and the host responds with an 8-bit Data consisting of a ‘1’
+ command(6:0). The SX8650 Acknowledges [A] and the host sends a stop [P].
The exact definition of command(6:0) can be found in section [4.9]
S SA W A CR
AP
Clock stretching
S:
Start condition
SA: SX8650 Slave Address(7:1)
W: '0'
A:
Acknowledge
CR: '1' + Command(6:0)
P:
Stop condition
From host to SX8650
From SX8650 to host
Figure 30. I2C host command
The sampling of the screen by the SX8650 and the host I2C bus traffic are events that might occur simultaneously. The
SX8650 will synchronize these events by the use of clock stretching if that is required. The stretching occurs directly after
the last received command bit (see Figure 30).
ACS Revision V2.15/October 2009
©2009 Semtech Corp.
Page 31
www.semtech.com