A82: ASM shells crashing calc


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A82: ASM shells crashing calc



I'm not very familiar with the methods the shells use to execute 
themselves, but here's a possible solution. As I understand it, a pointer 
in the RAM is changed to point to the ASM code of the shell, but this 
modification causes other problems such as the misreported variable sizes, 
the use of a "dummy" variable, and the frequent crashes. How about if the 
shell used this method to execute itself the first time after it was 
transferred to the calc, but when it was run the first time, it would 
install a TSR, and restore the changed pointer to its original state, so 
the crashing and misreported variable sizes would not occur. To run the 
shell again, the TSR would monitor for a combination of keys being held 
down. So for example, when the buttons PRGM and MATH are pressed together, 
the shell would launch.

I could be wrong about this, but it seems like it would work.
________________

Jeff Tyrrill
http://tyrrill-ticalc.home.ml.org/
http://ti-files.home.ml.org/