4-Port PoE Manager

Microsemi Proprietary and Confidential. PD69104B1/F Datasheet Revision 2.0

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The following illustration shows the master's read packet structure.

Figure 7 • Master's Read Packet Structure

The following illustration shows the master's write packet structure.

Figure 8 • Master's Write Packet Structure

3.15.2

Broadcast Support

All slaves answer a general address sent by the master. The general address is 7'h0.

Broadcast is for master writing only—read accesses are ignored in a broadcast transaction.

3.15.3

Auto Baud Rate Learning

PD69104B1/F has a self-learning baud rate mechanism that allows synchronizing all PD69104B1/F slaves

to the master’s "real" baud rate and thus working with a higher baud rate.

The first byte received by the slave is 8'hAA. At the rising or falling edge of each bit, an 8 MHz counter

starts counting the bit width (in a 125 ns resolution). The average width of the 8 header bits is the actual

bits rate. By using this mechanism, PD69104B1/F slaves can be synchronized with the master and set

back data at that rate. The header is a preamble bit that facilitates synchronization.

The following illustration shows the header bit width.