SETPR, SETPI, SETPB – Blocks for remote parameter setting

Block SymbolsLicensing group: STANDARD

Function Description
The SETPR, SETPI, SETPB and SETPS blocks are used for setting the parameters of other blocks in the model remotely. The only difference among the three blocks is the type of parameter which they are setting. The SETPR block is used for setting real parameters, the SETPI block for integer parameters, the SETPB block for Boolean parameters and the SETPS block for string parameters.

The blocks operate in two modes, which are switched by the SETF parameter. For $\mathtt{\text{SETF}}=\mathtt{\text{off}}$ the remote parameter sc is set to the value of the input signal p (or ip, P) at the start and every time when the input changes. If the SETF parameter is set to on, then the blocks work in one-shot write mode. In that case the remote parameter is set only when rising edge (off$\to$on) occurs at the SET input. Successful modification of the remote parameter is indicated by zero error output $\mathtt{\text{E}}=\mathtt{\text{off}}$ and the output y (or k, Y) is set to the value of the modified parameter. The error output is set to $\mathtt{\text{E}}=\mathtt{\text{on}}$ in case of write error.

The name of the remote parameter is determined by the string parameter sc (string connection), which has the form <block_path:parameter_name>. It is also possible to access individual items of array-type parameters (e.g. the tout parameter of the ATMT block). This can be achieved using the square brackets and item number, e.g. .ATMT:touts[2]. The items are numbered from zero, thus the string connection stated above refers to the third element of the array.

The path to the block whose parameter should be set can contain hierarchic levels separated by dots followed by the block name. The path can be either relative or absolute:

• Relative – starts at the level where the SETPR block (or SETPI, SETPB, SETPS) is located. The string has to be prefixed with ’.’ in this case. Examples of relative paths: ".GAIN:k", ".Motor1.Position:ycn".
• Relative to task – starts at the root level of the task where the SETPR block (or SETPI, SETPB, SETPS) is located. The string has to be prefixed with ’%’ in this case. Examples of paths: "%GAIN:k", "%Motor1.Position:ycn".
• Absolute – complete sequence of hierarchic levels down to the block. For referring to blocks located in the driver task (see the IOTASK block for details on configuration) the ’&’ followed by the driver’s name is used at the beginning of the absolute path. Examples of absolute paths: "task1.inputs.lin1:u2", "&EfaDrv.measurements.DER1:n".

The order and names of individual hierarchic levels are displayed in a tree structure in the REXYGEN Diagnostics program.

Warning: If the remote parameter is in a task other than the SETPx block, block execution is delayed until the remote task is completed. It is necessary to avoid the so-called race conditions and guarantee the correct value setting. Therefore, it is recommended to include the SETPx block in a slower task (longer period/execution time) and set parameter in a faster task (shorter period/execution time). In the opposite situation (e.g. the SETPx block in a faster task), the GETPx block should be used in a slower task.

Note: When using multiple SETPx blocks, it is not guaranteed that all data will be written to the remote task in the same tick. It is only guaranteed that the previous block will set a value in the same or previous period as the next block (the order of blocks execution can be checked in REXYGEN Diagnostics). To send multiple values in the same period, it is needed to use the Inport and Outport blocks or the SETPA block.

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