LOG – Write a log message

This block writes a user-defined message in the log module of Cockpit.

Numerical values can be inserted into the message using the conversion specifier “%f“, that will take to the value of the second input signal. This block only supports floating-point numbers. Optionally, the number of digits displayed after the decimal point can be specified using the precision modifier ".". Here are some examples:

Simulink block

Signal specification

• The first input is a trigger port that generates a log message when its value rises from a negative or zero value to a positive value.
• The second input is only visible when Include variables in message is checked. It is used to input numerical value(s) into the message. The value(s) are sampled when the log message is triggered.
  Its width is defined by the parameter Number of variables and must also correspond to the number of conversion specifiers contained in the message.

Parameters

• Log message is the message that will be displayed in the log module of Cockpit.
• String type indicates whether the Log message field contains a literal text string or an expression that should be evaluated.
• Severity defines the type of message (Info, Warning, or Error). The log module of Cockpit lets you filter the displayed message by severity.
• Include variables in message indicates if numerical values are inserted in the message using the %f placeholder. If checked, a second port appears to input the numerical values.
• Number of variables is the number of numerical values that are inserted into the message. This field is only visible if Include variables in message is checked.

PLECS block

Signal specification

• The first input is a trigger port that generates a log message when its value rises from a negative or zero value to a positive value.
• The second input is only visible when Include variables in message is checked. It is used to input numerical value(s) into the message. The value(s) are sampled when the log message is triggered.
• Its width is defined by the parameter Number of variables and must also correspond to the number of conversion specifiers contained in the message.

Parameters

• Log message is the message that will be displayed in the log module of Cockpit.
• String type indicates whether the Log message field contains a literal text string or an expression that should be evaluated.
• Severity defines the type of message (Info, Warning, or Error). The log module of Cockpit lets you filter the displayed message by severity.
• Include variables in message indicates if numerical values are inserted in the message using the %f placeholder. If checked, a second port appears to input the numerical values.
• Number of variables is the number of numerical values that are inserted into the message. This field is only visible if Include variables in message is checked.

C++ functions

int  Log_AddMsg(int msg_id, int sev, const char *msg);
Code language: C++ (cpp)

Log_SendMsg(int msg_id, float vars[]=nullptr, int n_vars=0);
Code language: C++ (cpp)

Example of use

tUserSafe UserInit(void)
{
    //...
    // Configure a warning message with a unique id of 0
    Log_AddMsg(0, 20, "Operating limits exceeded (V=%.3fV / I=%.3fA)");
    //...
    return SAFE;
}

tUserSafe UserInterrupt(void)
{
    //...

    static bool warning_message_sent = false;
    if(V_meas > 850 || I_meas > 40){
        float log_values[2];
        log_values[0] = V_meas;
        log_values[1] = I_meas;
        // Display the message in Cockpit
        if(!warning_message_sent) {
            Log_SendMsg(0, log_values, 2);
            warning_message_sent = true;
        }
    } else {
        warning_message_sent= false;
    }

    //...

    return SAFE;
}

Code language: C++ (cpp)