| ??? 02/22/05 18:53 Read: times |
#88178 - a dot matrix printer must be one task Responding to: ???'s previous message |
three distinct tasks, one of which was controlling motor speed, another was preparing print data, and the third was controling the print head pulse width. Do you disagree these are separate tasks?
yes, I disagree, the "task" is "print". The example you have given is a dot matrix printer controller and if you separate these 3 functions you will have no guarantee that "prepared print data" will be ready when the motor has located the printhead to a given position. Likewiase, if you separate tne functions you have no guarantee that the printhead is located where you want to be when you control the print head pulse width. So, as all depend on all, you can not split it. I am, of course, aware that you can make 'a' set a flag that 'b' wait for etc. and you can, of course design a printer where the motor stop and wait for "prepare print data", then "control the print head pulse width", then start the motor and repeat. I doubt you would sell many. The issue is that if the functions depend on each other, you can not separate them into "tasks". The example of Windoew where no "task" depend on the other, your ICE run fine even if you have IE running BECAUSE they do not depend on each other. Erik |
| Topic | Author | Date |
| please expalin RTOS, UnRTOS, MTOS... | 01/01/70 00:00 | |
| Os's | 01/01/70 00:00 | |
| thanks ...and now for Erik... | 01/01/70 00:00 | |
| MicroC O/S II works fine | 01/01/70 00:00 | |
| Threads? | 01/01/70 00:00 | |
| Threads, Real Time and Multitasking | 01/01/70 00:00 | |
| Just for clarification | 01/01/70 00:00 | |
| Multiprocessing | 01/01/70 00:00 | |
| Multiprocessing | 01/01/70 00:00 | |
| Further clarification | 01/01/70 00:00 | |
| Threads | 01/01/70 00:00 | |
| Windoze | 01/01/70 00:00 | |
| More Windoze | 01/01/70 00:00 | |
| Ah... | 01/01/70 00:00 | |
| Basic Info | 01/01/70 00:00 | |
| extract from the above with translation | 01/01/70 00:00 | |
| Completed | 01/01/70 00:00 | |
| who are we | 01/01/70 00:00 | |
Tics | 01/01/70 00:00 | |
| the rest | 01/01/70 00:00 | |
| But wait..there's more! | 01/01/70 00:00 | |
| Real Time Info | 01/01/70 00:00 | |
| hard/soft | 01/01/70 00:00 | |
| Real Time Info | 01/01/70 00:00 | |
| m,y opinion | 01/01/70 00:00 | |
| why so late | 01/01/70 00:00 | |
| one more thing | 01/01/70 00:00 | |
| Architecture Independent | 01/01/70 00:00 | |
| just to clarify | 01/01/70 00:00 | |
| No. | 01/01/70 00:00 | |
| RTOS on a 51?? | 01/01/70 00:00 | |
| not the thing but the word | 01/01/70 00:00 | |
| A Distinction (with a difference) | 01/01/70 00:00 | |
| Tasks or Applications? | 01/01/70 00:00 | |
| Multi Tasking | 01/01/70 00:00 | |
| a dot matrix printer must be one task | 01/01/70 00:00 | |
| One task or three | 01/01/70 00:00 | |
| pray explain | 01/01/70 00:00 | |
| Tasks and Functions | 01/01/70 00:00 | |
| we are getting closer | 01/01/70 00:00 | |
| Not that far apart | 01/01/70 00:00 | |
| I doubt we are | 01/01/70 00:00 | |
| discussed | 01/01/70 00:00 | |
| TTCS | 01/01/70 00:00 |