| ??? 02/01/05 21:52 Read: times |
#86322 - fact piece Responding to: ???'s previous message |
this is simply because an RTOS is not fast enough for this type of application
Let us take a case of some industrial control and also display something on a LCD. With a URTOS the LCD "task" will be allotted, say 1ms of every 10ms. This time is not available to process the control stuff. I know that some URTOSs have priority, but there we start to lose time in priority determination and hang on priority inversion, so the case is not much better there. I know of no URTOS that can "switch a task" as fast as a '51 can vector to an interrupt. In a "normal system" the control stuff get processed immediately (typically in an ISR) and the LCD get processed "when time permit" (so what if it takes a full second to update the LCD, no user will see/complain). That is fact, not opinion. Erik |
| Topic | Author | Date |
| Computed Call | 01/01/70 00:00 | |
| Computed Call | 01/01/70 00:00 | |
| simulate an LCALL @A+DPTR instruction? | 01/01/70 00:00 | |
| Solution | 01/01/70 00:00 | |
| Computed LCALL | 01/01/70 00:00 | |
| Computed LCALL | 01/01/70 00:00 | |
| Table offset | 01/01/70 00:00 | |
| x2, not x3 | 01/01/70 00:00 | |
| what is the problem | 01/01/70 00:00 | |
| My Problem | 01/01/70 00:00 | |
| never heard of it | 01/01/70 00:00 | |
| It is....... | 01/01/70 00:00 | |
| RTOS | 01/01/70 00:00 | |
| 8051 RTOs Limitations/Issues/Opportunity | 01/01/70 00:00 | |
| How? | 01/01/70 00:00 | |
| Decisions, decisions | 01/01/70 00:00 | |
| Small systems - task scheduling | 01/01/70 00:00 | |
| Worth it? | 01/01/70 00:00 | |
| Scheduler | 01/01/70 00:00 | |
| Scheduler | 01/01/70 00:00 | |
| running small in a big way | 01/01/70 00:00 | |
| Example | 01/01/70 00:00 | |
| in very small chips | 01/01/70 00:00 | |
| In all sorts of sizes of chips | 01/01/70 00:00 | |
| time dependednt | 01/01/70 00:00 | |
| RTOS or Not | 01/01/70 00:00 | |
| opinion piece | 01/01/70 00:00 | |
| fact piece | 01/01/70 00:00 | |
| Opinion piece | 01/01/70 00:00 | |
| suggestion piece | 01/01/70 00:00 | |
| reasons | 01/01/70 00:00 | |
| Polite discussion | 01/01/70 00:00 | |
| Politeness | 01/01/70 00:00 | |
| Thanks | 01/01/70 00:00 | |
| Politeness | 01/01/70 00:00 | |
| What are you Rabbiting on about? | 01/01/70 00:00 | |
| Close but no Cigar | 01/01/70 00:00 | |
| Rabbit food | 01/01/70 00:00 | |
| Plessey | 01/01/70 00:00 | |
| small world | 01/01/70 00:00 | |
Smaller than you imagine! | 01/01/70 00:00 | |
| I use the computed LCALL ... | 01/01/70 00:00 | |
| go it | 01/01/70 00:00 | |
| Call tabs in-line | 01/01/70 00:00 | |
| abbreviated | 01/01/70 00:00 | |
| ... and further optimized... | 01/01/70 00:00 | |
| has been already disscussed | 01/01/70 00:00 | |
| Scheduler of course | 01/01/70 00:00 | |
| Scheduler | 01/01/70 00:00 |