 | | Re: JRM code and Reset —Dan Gates
|
| | | Wow, What a bugger! This is one of the strangest cases I've seen. Works fine while connected, but not when reset. Works fine on my board either way. Memory and 68HC11 have been traded out. Scope shows no voltage drop at Mem-power durring reset. Both (...) (23 years ago, 2-Jan-02, to lugnet.robotics.handyboard)
|
| | | |
| | | | | Re: JRM code and Reset —John R. McDaniel
|
| | | | Dan, Yes, I did cut the trace for external motor power. I know the HB and the motor power "+" sources are isolated because I not only checked with a VOM, but I removed the motor supply batteries and when I run my motor test program (remember, no (...) (23 years ago, 3-Jan-02, to lugnet.robotics.handyboard)
|
| | | | |
| | | | | | Re: JRM code and Reset —Dan Gates
|
| | | | John, I just did the same test, I think what Fred was saying is that IC sets the 0x8000 to accept a startup program if one is loaded. If I poke a 0 to that address then load any program it sets back to 1. I think he was wandering if your IC version (...) (23 years ago, 3-Jan-02, to lugnet.robotics.handyboard)
|
| | | | |
| | | | | | 0x8000 and main() —John R. McDaniel
|
| | | | Dan, Perhaps I'm misinterpreting what you mean by "a startup program". To me, a "startup program" means there is a file downloaded to the HB that contains a " main() " function, i.e., a function which will automatically be executed upon startup (...) (23 years ago, 3-Jan-02, to lugnet.robotics.handyboard)
|
| | | | |
| | | | | | Re: 0x8000 and main() —Dan Gates
|
| | | | John, I think it lies in the Pcode, in other words if the pcode sets the 0x8000 to 1 then any program loaded that has main() in it will auto run at startup. If the pcode does NOT set 0x8000 to 1 then no matter what you have loaded as a program it (...) (23 years ago, 3-Jan-02, to lugnet.robotics.handyboard)
|
| | | | |
| | | | | | Re: 0x8000 and main() —Fred G. Martin
|
| | | | I don't think this is quite it -- IC sets the byte if there's a main fcn. It also sets up some code so that main fcn gets run. Fred (...) (23 years ago, 3-Jan-02, to lugnet.robotics.handyboard)
|
| | | | |
| | | | | | Re: 0x8000 and main() —John R. McDaniel
|
| | | | Fred and Dan, For some reason, I'm apparently having trouble explaining my findings, doing something wrong -- or not understanding what Fred is telling me. Now that my HB runs " main() " functions just fine upon powerup reset, I did my experiment on (...) (23 years ago, 5-Jan-02, to lugnet.robotics.handyboard)
|
| | | | |
| | | | | | Re: 0x8000 and main() —John R. McDaniel
|
| | | | Fred, Dan, and Chuck, Thanks to an email from Chuck McManis (thanks, Chuck), I now have a better understanding of what's going on with respect to the main() function and memory location 0x8000. Chuck asked me if the main() function is executed after (...) (23 years ago, 6-Jan-02, to lugnet.robotics.handyboard)
|
| | | | |
