8 bit Data Format:

In the 8 bit data format, the byte is comprised of 8 data bits. Since there is no way to discriminate a header byte from an operand byte, a header byte is assumed to be any byte that reaches the receiver while on idle (no serial activity for more than 20 ms). Once the entire message is over, the communication channel must allow enough time for the receiver to time out and go into idle mode. This measure has been put into place so that operand bytes do not get confused as Header Bytes.

9 bit Data Format:

The 9 bit data format is the most secure of both options since it incorporates true addressing. In this scenario, the byte is comprised of an address bit and 8 data bits. The address bit is 1 for a Header Byte and 0 for any Operand Byte. This makes it really easy for the receiver to discriminate between Header and Operand bytes. Although receiver time out is still available to report Non Acknowledge States, the communication channel does not need to wait time from one message to the next. This feature alone allows for faster communications.

[Data Format] [Configurations] [Mode Bits] [Handshaking]

[Data Format] [Configurations] [Mode Bits] [Handshaking]

Last Updated on Jan 10, 2008

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