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Description of the DP Functions, Data, and Error Codes
DP Base Programming Interface for CP 5613/CP 5614
C79000-G8976-C108-01
203
Structure of an ID Byte
Each bit has a special meaning.
Bit Meaning
0 to 3
Number of data units - 1
3 means for example 4 data units of the length specified in bit 6
4 and 5
Input/output
Bit 5 Bit 4 Meaning
0 0 does not occur (see below)
0 1 Input
1 0 Output
1 1 input/output
6
Length of the data units
0 means: the data unit is in bytes
1 means: the data unit is 2 bytes
7
Consistency
0 means: byte or word consistency
1 means: consistency over the entire length
Structure of a Special ID Byte
Special identifier formats allow the configuration to be extended by increasing the
flexibility. Each bit in the ID byte has a special meaning.
Bit Meaning
0 to 3 Length of the vendor-specific data
These bits contain the length of the vendor-specific data.
4 and 5 These bits always have the value 00.
6 and 7
Input/output
Bit 7 Bit 6 Meaning
0 0 No optional bytes follow
0 1 1 length byte for inputs follows
1 0 1 length byte for outputs follows
1 1 This is followed by
1 length byte for outputs
1 length byte for inputs
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