> It might be worth reconsidering how unconnected pins are handled. Letting > something read or write to dummy can cause nasty bugs. That's particularly > true for writing to dummy.
Reading a unconnected pin should result at least in a warning. I guess this could be checked beforehand as soon as linuxcnc is started. > Checking for a null pointer is pretty fast with today's machines -- even > with the ARM and other little processors. Yes checking is fast but the best is to allow only valid assignment because it make software simpler and avoid the problem did not remember to check everywhere. Only a few languages however have good type checking. > I wrote a similar system back in the early 70's (the processor was an Intel > 8080). The model didn't differentiate between signals and parameters. > Everything was implemented as a (logical) value in a named register. The > last writer of the value won. There were four thread priorities that ran > asynchronously. That could lead to some "interesting" bugs. That's why global variables or other form av similar global storage should not be used. Nicklas Karlsson ------------------------------------------------------------------------------ _______________________________________________ Emc-developers mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-developers
