Datasheet

Jon Waddington
65
4.6 X10
The testing of the X10 commands proved that they were reliable. The modules
performed their required functions without a problem although they were quite slow to
respond, taking approximately one second to perform the desired function due to the
data transfer speed being limited to the 50Hz mains frequency.
4.7 I2C
The I2C example in this section show how the Propeller communicates with the P CF8563
IC to read the minute register.
Figure 4.7.1 shows a waveform of the Propeller sending the write address of the
PCF8563. The top waveform (SDA) shows the serial data and the bottom waveform
(SCK) shows the clock signal.
The waveform begins with the Propeller pulling the SDA line low while SCK remains high.
This is the Start condition. The PCF8563 then reads the incoming byte and transmits an
acknowledge bit. The Propeller then understands that the PCF8563 is present on the I2C
line.
SCK
SDA
Start
Condition
0
0
0
0
1
0
1
1
Acknowledge
0xA2
Figure 4.7.1. I2C Waveform Sending the
Address 0xA2