| ??? 01/16/07 08:16 Read: times |
#130852 - Bad practice... Responding to: ???'s previous message |
Stefan Kanev said:
I have some (my) DOS programs, which access COMports directly. This was never a good idea: I said:
The use of hard-coded addresses and direct access to the physical hardware is a key reason why old DOS software no longer works under modern operating systems like Win-NT and later...
Even in the days of DOS, such applications were inflexible, non-portable and often conflicted with other stuff on the PC. http://www.8052.com/forum/read.phtml?id=130849 Stefan Kanev said:
These programs are working under Win98 too. I dont know why, but under XP these programs at least write into TXbuf register, there are problems with interrupt handling. See above! XP is a multi-tasking operating system; it can even support multiple users on the same PC - MS-DOS was single-user, single-task. Clearly, no multi-tasking multi-user system can ever allow any application or user to just go willy-nilly accessing arbitrary physical hardware! Chaos would result! Stefan Kanev said:
On other hand - there is still available BIOS - bytes can be sended/received , using BIOS interrupts. These interrupts are still accessible under win98, a cant remember about XP. You need to use the proper drivers under NT et al; you should also have done it under 98! |
| Topic | Author | Date |
| doubt about ports | 01/01/70 00:00 | |
| and one more doubt | 01/01/70 00:00 | |
| Programming the PC | 01/01/70 00:00 | |
| Off Topic | 01/01/70 00:00 | |
| Wrong forum | 01/01/70 00:00 | |
| Win ports | 01/01/70 00:00 | |
| Bad practice... | 01/01/70 00:00 | |
| Bad practice | 01/01/70 00:00 | |
| some thoughts | 01/01/70 00:00 | |
| Do not hard-code adresses! | 01/01/70 00:00 | |
| You need to tell us more ... | 01/01/70 00:00 | |
| MS-DOS | 01/01/70 00:00 | |
| why? | 01/01/70 00:00 | |
| Misunderstanding ? | 01/01/70 00:00 | |
| Not quite so | 01/01/70 00:00 | |
| a parallel in '51 | 01/01/70 00:00 | |
| Sharing | 01/01/70 00:00 | |
| OK, the sad facts | 01/01/70 00:00 | |
| MS-DOS will allow and do anything the PC can do | 01/01/70 00:00 | |
| ...and the reason is ... | 01/01/70 00:00 | |
| If Windows were truly multi-user/multitasking ... | 01/01/70 00:00 | |
| it's broken | 01/01/70 00:00 | |
| So much for the "Good Old Days" | 01/01/70 00:00 | |
| Yes, and the ones that worked, worked really well | 01/01/70 00:00 | |
The Right one | 01/01/70 00:00 |