- D2 may not be preserved on exit. See QL World, December 1986 Page 43.
- A1 is not preserved unless a TRAP #4 was done first!!!
Cheers,
Norm.
There is a Trap#4, just before the Trap#2. And I get the problem.NormanDunbar wrote:Just checked my QDOS Companion too. My notes for IO_OPEN (Page 39) are as follows:
It seems I had problems too, some time back.
- D2 may not be preserved on exit. See QL World, December 1986 Page 43.
- A1 is not preserved unless a TRAP #4 was done first!!!
Cheers,
Norm.
That's Norman's docs that say "preserved after TRAP#4" - Other's don't. I guess that's more of an observation than a system commitment.Martin_Head wrote:There is a Trap#4, just before the Trap#2. And I get the problem.NormanDunbar wrote:Just checked my QDOS Companion too. My notes for IO_OPEN (Page 39) are as follows:
It seems I had problems too, some time back.
- D2 may not be preserved on exit. See QL World, December 1986 Page 43.
- A1 is not preserved unless a TRAP #4 was done first!!!
Cheers,
Norm.
From a JS disassembly I can determine that A1 isn't preserved at all. The only thing a TRAP#4 does is to set a bit in the job header, which is read by the subsequent TRAP#2. Unfortunately, the entry code of the latter trap uses A1 to locate and read this bit (for those interested, it starts at $32A2). Ironically, A1 is saved in the code afterwards which is of course of no use.tofro wrote: That's Norman's docs that say "preserved after TRAP#4" - Other's don't. I guess that's more of an observation than a system commitment.