DT-INTs What's legal in an INT handler?

[Bruce]

Hi Al,

No problem at all with your code. You GOSUB outside the int handler, and you RETURN right back to it, so this isn't a problem.

The problem is only when you GOTO (or GOSUB) to another routine, outside an interrupt handler, and you do NOT return to it where it restores saved registers, and issues a RETFIE command.

You show a DT Interrupt handler. You may not see it, but i guarantee theres a lot of code on exit from a DT interrupt routine
that's restoring system file registers.