Datasheet

Jon Waddington

The address and contents of the registers are shown below in figure 3.8.2.1 [37].

The values in the registers are in Binary Coded Decimal (BCD), meaning that each digit,

from 0 to 9, is represented by 4 bits. The lower 4 bits in the registers represent the units

digit and the upper bits represent the tens digit. The Table below shows a decimal value

of 34 in BCD. The 4 MSBs (the tens) have a value of 3 and the LSBs (the units) have the

value of 4.

Figure 3.8.2.2 shows an example of the Propeller, reading the minute register of the

PCF8563.

Figure 3.8.2.2. An Example of an I2C Message

Figure 3.8.2.1. The addresses and Contents of the PCF8563’s Registers

Bit 7

Bit 6

Bit 5

Bit 4

Bit 3

Bit 2

Bit 1

Bit 0

BCD

Decimal