Local process image in delivery state
The process image of the Bus Terminal Controller consists of input, output and flag area. In addition, there are unallocated data without fixed address. They are created without specifying an address. For these variable types the memory allocation is as follows:
- BCxx50 48 kbyte,
- BC9x20 128 kbyte,
- BXxx00 256 kbyte.
The maximum size of a variable or structure (array) is 16 kbyte. For the allocated data 2048 bytes of input data and 2048 bytes of output data are available. The Bus Terminal Controller has 4 kbyte of memory allocated for the flag area.
In the delivery state (default configuration) of the BX/BCxx50, fixed addresses are allocated for all connected Bus Terminals. The data for PROFIBUS communication start from address offset 1000dec. The length of the PROFIBUS data depends on the number of configured data. The maximum is 244 bytes for the BX3100 and 128 bytes for the BC3150.
Inputs | Outputs |
|---|---|
Bus Terminal %IB0 ... | Bus Terminal %QB0 ... |
PROFIBUS DATA (PLC variable) %IB1000 ... | PROFIBUS DATA (PLC variables) %QB1000 ... |
... %IB2047 Maximal | ... %QB2047 Maximal |
Addressing of the connected Bus Terminals
The default setting is for all the connected Bus Terminals to be assigned to the local process image. Mapping within the Bus Terminal Controller is carried out according to the following rule:
First all the complex Bus Terminals, in the sequence they are physically inserted, followed by the digital Bus Terminals which are filled to a byte. The default mapping of the complex Bus Terminals is:
- complete evaluation
- Intel format
- Word alignment
Example structure
Bus Terminal Controllers: 1 x BX/BCxx50
Position 1: 1 x KL1012
Position 2: 1 x KL1104
Position 3: 1 x KL2012
Position 4: 1 x KL2034
Position 5: 1 x KL1501
Position 6: 1 x KL3002
Position 7: 1 x KL4002
Position 8: 1 x KL6001
Position 9: 1 x KL9010
Process image
|
Bus Terminal | Position | Input image | Output image |
|---|---|---|---|
KL1501 | 5 | %IB0...%IB5 | %QB0...%QB5 |
KL3002 | 6 | %IB6...%IB13 | %QB6...%QB13 |
KL4002 | 7 | %IB14...%IB21 | %QB14...%QB21 |
KL6001 | 8 | %IB22...%IB29 | %QB22...%QB29 |
KL1012 | 1 | %IX30.0..30.1 | - |
KL1104 | 2 | %IX30.1..30.5 | - |
KL2012 | 3 | - | %QX30.0..30.1 |
KL2034 | 4 | - | %QX30.2..30.5 |
KL9010 | 9 | - | - |