I know there're knowledgeable guys here, please help solving an issue... There're call vectors (hooks) in Fxxx area in RAM, and I want to set it to call my own code in some slot. Vector occupies 5 bytes enough to hold rst30 and ret. But it will call ROM, which in its turn will need to call next subs in the chain. But to call next sub, ROM should have saved previous call pointer somewhere.
The question is - where to save it? Is there any valid / approved way for ROMs to do that?
Saving that data "somewhere in RAM" is a bad workaround as it can be overwritten by user/another system call and machine may crash...
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