EXRAIL START() Not Passing Loco to New Task

[kallelix]

Hi,

I've encountered an issue with EXRAIL: According to the documentation, there are several references stating that START() passes the locomotive from the current task to the new one — for example:
https://dcc-ex.com/exrail/getting-started.html#drive-away-feature

However, this doesn’t seem to work as expected. I looked into the current implementation of START():
case OPCODE_START: { int newPc=routeLookup->find(operand); if (newPc<0) break; new RMFT2(newPc); } break;

Not surprisingly, this doesn’t pass the loco to the new task. I tried modifying it like this:

case OPCODE_START: { int newPc=routeLookup->find(operand); if (newPc<0) break; RMFT2* newtask=new RMFT2(newPc); // create new task newtask->loco=loco; } break;
With this change, it works as expected.

Is this the intended behavior, or is this an oversight?

Regards,
Kristian

[habazut]

This should be enough?

diff --git a/EXRAIL2.cpp b/EXRAIL2.cpp
index 0982510..077681a 100644
--- a/EXRAIL2.cpp
+++ b/EXRAIL2.cpp
@@ -997,7 +997,7 @@ void RMFT2::loop2() {
     {
       int newPc=routeLookup->find(operand);
       if (newPc<0) break;
-      new RMFT2(newPc);
+      new RMFT2(newPc, loco);
     }
     break;
     

Harald.

[kallelix]

I don't find an implementation for this constructor. It is declared, but not implemented.

Suggestion: START() can simply call the static method createNewTask((int route, uint16_t cab)

[Asbelos]

I vaguely recall that I did pass the loco when I first wrote it but several users fell in to the trap that this creates.
Because this leaves two separate tasks operating the same loco, if either of them reaches a DONE then the loco stops.

There really needs to be 3 versions of this command,

1. no pass of loco
2. pass loco ro another task
3. share loco with another task.

I think I would prefer to change the documentation here, and perhaps implement the other 2 versions with new commands

[kallelix]

I understand.

Maybe a SENDCURRENTLOCO(route) will do the job.

I don't know about the sharing case... Necessary?

[habazut]

I don't find an implementation for this constructor.

 class RMFT2 {
   public:
    static void begin();
    static void loop();
    RMFT2(int progCounter, int16_t cab=0);
// ...                      ^^^^^^^^^^^^^

But I agree that a docu change is better in this case.

[kallelix]

ok, the method signatur changed between devel and master.