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SerialLite II Protocol Reference Manual

SerialLite II Specification

There are two categories of code group:

■ Data code-groups: Any 8-bit byte can be converted into a 10-bit

encoded character.

■ Special code-groups: A limited number of 8-bit values can be

converted into 10-bit control characters.

When a control byte is to be encoded, a separate signal must be asserted

to inform the encoder that it must generate a special code-group, not a

data code-group.

Notation Convention

The 8B/10B transmission scheme uses letter notation to describe the bits

of an unencoded information byte and the one-bit control variable. The

control variable is set to 1 to select a K value from the special code-groups;

it is not set for the D value of the data code-groups. Code-groups are

indicated by the notation ‘Dx.y’ or ‘Kx.y’. See “8b/10b Code Groups” on

page 2–75 for a listing of the possible values and encodings.

The bit notation of HGF EDCBA is used to indicate the bits of the

unencoded 8-bit value, where A is the least-significant bit (LSB), as shown

in Figure 2–6.

Figure 2–6. Character Notation Example of D30.4

The HGF EDCBA bits are translated to the abcdei fghj bits of the 10-bit

transmission code-groups, as shown in Figure 2–7.

Figure 2–7. Code-Group Notation Example of D30.4

HGF EDCBADx.y

D30.4

4 30 100 11110

fghjabcdei

0010011110

1101100001

RD-

RD+

1 2 ... 12 13 14 15 16 17 18 19 20 21 22 ... 83 84

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