Timeline for PDP-11 instruction set inconsistencies
Current License: CC BY-SA 4.0
10 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| Feb 3, 2024 at 19:40 | comment | added | dave | Intel usage irritates me - the INT instruction is a trap, not an interrupt :-) | |
| Feb 3, 2024 at 18:39 | comment | added | Anixx | @dave OK, revert | |
| Feb 3, 2024 at 18:39 | history | edited | Anixx | CC BY-SA 4.0 | deleted 5 characters in body |
| Feb 3, 2024 at 17:41 | comment | added | dave | 'Trap' was correct before the last edit. It's an "odd address trap" (because synchronous with instruction execution), not an interrupt (because not caused by an external signal). See page 128 in this handbook. | |
| Feb 3, 2024 at 16:50 | history | edited | Anixx | CC BY-SA 4.0 | added 5 characters in body |
| Feb 3, 2024 at 15:35 | comment | added | dave | Again as far as I recall - byte move to a register always sign-extended. This sticks in my mind because I almost never wanted it to. | |
| Feb 3, 2024 at 15:33 | history | edited | dave | CC BY-SA 4.0 | edited body |
| Jan 6, 2022 at 0:54 | comment | added | dave | re continuing from the closest even address - which is closer to address 12345 -- 12344 or 12346? :-) As far as I recall on the 11/24, the low bit was ignored, i.e., it would be 12344. This was widely seen as an annoying misfeature, since some bugs would not be detected. | |
| Jun 28, 2018 at 13:02 | history | edited | Anixx | CC BY-SA 4.0 | added 131 characters in body |
| Jun 28, 2018 at 12:37 | history | answered | Anixx | CC BY-SA 4.0 |