通过 CAPL 发送消息

Question

I am sending a CAN message from a database,

variables
{
  message PNHV_Energy msg;
}

output (msg);

This message has 5 signals

signal A: 1 bit - startbit is 28
signal B: 3 bit - startbit is 29
signal C: 16bit - startbit is 48
signal D: 8 bit - startbit is 32
signal E: 8 bit - startbit is 40

How do I construct this and send it? The problem I face is in signal A and signal B, which are packed in one byte at location A: 1bit-28. signal B: 3bit-29 to 30.

what value for byte 3 should be set in?

msg.byte(3)= ?

It uses a little-endian format.

Answer 1

Variables of type message are classes in CAPL. If drawed from a valid CAN database, they come pre-packed with all the signals associated with them. Let us see an example

Variables
{
    message PHNV_Energy msg;
}

on start {
    /* at the beginning of measurement, set the signals */
    msg.A = 0x00;
    msg.B = 0x00;
    msg.C = 0x00;
    ...
}

on message * {
    /* every time a message is received by our CAPL program node */
    output(message);
}

This is a much easier way to set your message, compared to your solution: you no longer need to worry about this

The problem i face is in signal A and signal B, which are packed in one byte at location signal A: 1bit-28. signal B: 3bit-29 to 30.

Answer 2

Found an answer for the question,

Variables
{
    message PNHV_Energy msg; //Message to be sent from database
}

send_message()
{
    msg.byte(0)=0x0;  //0x00
    msg.byte(1)=0x0;  //0x00
    msg.byte(2)=0x0;  //0x00
    msg.byte(3)=0x20; //bit29-31: signal 1, bit 28: signal 2
    msg.byte(4)=0xFF; //FF to be sent at byte4: signal 3
    msg.byte(5)=0xFF; //bit 40 to bit 47: signal 4
    msg.byte(6)=0x10; //bit 48-51:0 bit52-55:1: signal 5
    msg.byte(7)=0x27; //bit 56-59:7 bit60-63:2: signal 5

    output (msg); // output Message
}