| ??? 11/19/11 20:08 Read: times |
#184813 - Seems a little harsh Responding to: ???'s previous message |
Per Westermark said:
It probably took two years, because either the data sent out changed or you handling of the data (master or slave side) changed because of the actual values. Or maybe the processors didn't run with crystals (except for the RTC) and the baudrate drifted slightly.
The issue here is that the extra ms needed means your software wasn't rugged enough. For two years, it was running on the margin, but you had failed to identify this critical flaw. It's no different from having a design running at just below the temperature where it fails, or at just the limit of how low voltage the processor can work with. All software development for embendded projects needs to set up a long list of critical limits, and then try to validate that there are ample safety margins. It's important to know that the slaves have whatever safety margin they need when picking up every single byte from the UART. Did you test with a higher baudrate or shorter delays than what you used for the final release? Per, You are pushing a bit toward making it sound like Mahmood is supposed to go sit in the corner on the stool and wear the tall hat. The fact of the matter is that it is hard to identify the long list of validation criteria for every aspect of some software. Of course it is easy to make judgement after the fact when hearing about the problem(s). But everyone ends up discovering this sort of thing in stuff that they have made. Part of the process at getting good at this embedded firmware art is having to slog through problems, correct them and then tuck that learning into our satchel of knowledge. Michael Karas |
| Topic | Author | Date |
| NXP Promises ARM Cortex-M0 in DIL Package! | 01/01/70 00:00 | |
| Amazing! I thought DIL was DEAD. | 01/01/70 00:00 | |
| Me too! | 01/01/70 00:00 | |
| Hmm.. | 01/01/70 00:00 | |
| maybe | 01/01/70 00:00 | |
| dsPIC is a waste of time | 01/01/70 00:00 | |
| We Await The Results... | 01/01/70 00:00 | |
| Which one(s)? | 01/01/70 00:00 | |
| two | 01/01/70 00:00 | |
| Why so long? | 01/01/70 00:00 | |
| Well | 01/01/70 00:00 | |
| Two years | 01/01/70 00:00 | |
| Answers | 01/01/70 00:00 | |
| But what delays did you try before original release? | 01/01/70 00:00 | |
| shorter delays | 01/01/70 00:00 | |
| good thinking | 01/01/70 00:00 | |
| Can't get the error | 01/01/70 00:00 | |
What changed? | 01/01/70 00:00 | |
| Seems a little harsh | 01/01/70 00:00 | |
| Never blame manufacturer without proofs | 01/01/70 00:00 | |
| Proven Product Syndrome | 01/01/70 00:00 | |
| My response ... | 01/01/70 00:00 | |
| No Offense | 01/01/70 00:00 | |
| What I Do and Not Do | 01/01/70 00:00 | |
| NXP are mistaken | 01/01/70 00:00 |