| 89C2051 oscillator does not oscillate (?) | | 01/01/70 00:00 |
| Capacitor value? | | 01/01/70 00:00 |
| 20-40pF indeed | | 01/01/70 00:00 |
| it might be the crystal | | 01/01/70 00:00 |
| Probably not | | 01/01/70 00:00 |
| because it\'s crap | | 01/01/70 00:00 |
| Not same position | | 01/01/70 00:00 |
| one cap or two makes most probably no difference.. | | 01/01/70 00:00 |
| Not on the pins | | 01/01/70 00:00 |
| I'd recomend you re-read the spec's ... | | 01/01/70 00:00 |
| It's the same Vcc | | 01/01/70 00:00 |
| Hhm...I wouldn't recommend this paralleling | | 01/01/70 00:00 |
| hummm... really? In what frequency range? | | 01/01/70 00:00 |
| The inductance of the left resonating with... | | 01/01/70 00:00 |
| interesting | | 01/01/70 00:00 |
| Spice models | | 01/01/70 00:00 |
| Thanks, Kai. | | 01/01/70 00:00 |
| Numerical calculation, some examples... | | 01/01/70 00:00 |
| Wrong reset scheme! | | 01/01/70 00:00 |
| 10µF reset capacitor to Vcc | | 01/01/70 00:00 |
| Isn't that the mfg's recommended circuit? | | 01/01/70 00:00 |
| Which do you mean? | | 01/01/70 00:00 |
| 10 uF to Vcc and 8.2K (built-in?) to GND | | 01/01/70 00:00 |
| no, it is not | | 01/01/70 00:00 |
| If it's in nearly every datasheet ... | | 01/01/70 00:00 |
| this is your perception of the things, Richard | | 01/01/70 00:00 |
| Here we go again ... | | 01/01/70 00:00 |
| ... and again... | | 01/01/70 00:00 |
| I don't know what to say ... | | 01/01/70 00:00 |
| there is NO out of spec power supply | | 01/01/70 00:00 |
| Not only... | | 01/01/70 00:00 |
| Not allways | | 01/01/70 00:00 |
| Have you seen evidence of improvement? | | 01/01/70 00:00 |
| Wider spectrum | | 01/01/70 00:00 |
| maybe ratio of good/bad crystals is the same... | | 01/01/70 00:00 |
| In all the various designs I produced ... | | 01/01/70 00:00 |
| Never had a failure until now | | 01/01/70 00:00 |
| I know of lots of crystal problems... | | 01/01/70 00:00 |
| Could be, but I've never encountered it ... | | 01/01/70 00:00 |
| %$#@! Double-post again ... ... | | 01/01/70 00:00 |
| ^%$#@! double-post ... | | 01/01/70 00:00 |
| If the datasheet says 1 ms ... | | 01/01/70 00:00 |
| more about locomotives | | 01/01/70 00:00 |
| symptoms suggest ... | | 01/01/70 00:00 |
| steam locomotives | | 01/01/70 00:00 |
| I like the steam locomotives | | 01/01/70 00:00 |
| So do I | | 01/01/70 00:00 |
| me too, said the dog | | 01/01/70 00:00 |
| The kids should be smarter than that! | | 01/01/70 00:00 |
| kids are kids | | 01/01/70 00:00 |
| It might not be a clock problem | | 01/01/70 00:00 |
| Does not work, sorry | | 01/01/70 00:00 |
| Bad Connections or Crystal ? | | 01/01/70 00:00 |
| A picture may be useful | | 01/01/70 00:00 |
| Breadboards are highly unsuited for micros!! | | 01/01/70 00:00 |
| Makes sense | | 01/01/70 00:00 |
| breadboards are highly unsuited for ANYTHING! | | 01/01/70 00:00 |
| Not at all! | | 01/01/70 00:00 |
| If you look at the pictures you can see why. | | 01/01/70 00:00 |
| Yes, it doesn\'t look properly, but... | | 01/01/70 00:00 |
| It's too risky! | | 01/01/70 00:00 |
| What is the purpose of your posts?? | | 01/01/70 00:00 |
| My purpose is to point out that there are flaws | | 01/01/70 00:00 |
| *** THE PICTURES *** | | 01/01/70 00:00 |
| Problem may be breadboard | | 01/01/70 00:00 |
| Breadboard correction | | 01/01/70 00:00 |
| How I programmed the 2051 | | 01/01/70 00:00 |
| Must be continuous | | 01/01/70 00:00 |
| there is a good english word \'IS\" | | 01/01/70 00:00 |
| I have the same thing running on my desk... | | 01/01/70 00:00 |
| really ? | | 01/01/70 00:00 |
| Sadly, it's a trade name | | 01/01/70 00:00 |
| yea, but... | | 01/01/70 00:00 |
| again, replacing one uncertainty with another | | 01/01/70 00:00 |
| I see two points | | 01/01/70 00:00 |
| When you\'re ready to give up ... try this! | | 01/01/70 00:00 |
| wow | | 01/01/70 00:00 |
| use the unbuffered parts | | 01/01/70 00:00 |
| It works fine with S, LS, HC, AC, HCT, ACT, etc | | 01/01/70 00:00 |
| It's not so foolproof | | 01/01/70 00:00 |
| I've had pretty good results ... | | 01/01/70 00:00 |
| Many thanks, I'll try some of your tips... | | 01/01/70 00:00 |
| Maybe your AT89C2051 is just damaged? | | 01/01/70 00:00 |
| Overtone | | 01/01/70 00:00 |
| 89S51/52 are much more stable | | 01/01/70 00:00 |
| Can you still (re-) program it | | 01/01/70 00:00 |
| Let's hope that Rubem will come back ... | | 01/01/70 00:00 |
| Hi again, sorry | | 01/01/70 00:00 |
| Even with no breadboard | | 01/01/70 00:00 |
| What has the programmer to do with the oscillator? | | 01/01/70 00:00 |
| The chip is fine | | 01/01/70 00:00 |
| What will that tell you about the oscillator? | | 01/01/70 00:00 |
| It is time to tell the manufacturer, that... | | 01/01/70 00:00 |
| oscillator of 2051? | | 01/01/70 00:00 |
| Sorry, maybe I was too harsh | | 01/01/70 00:00 |
| The MCU and crystals are all working for sure | | 01/01/70 00:00 |
| It was not the 7805 | | 01/01/70 00:00 |
| because you shook/dropped/kicked it | | 01/01/70 00:00 |
| 7805 decoupling | | 01/01/70 00:00 |
| LM79XX need a different treatment! | | 01/01/70 00:00 |
| Good news | | 01/01/70 00:00 |
| Is this >good news< ?? | | 01/01/70 00:00 |
| Have you considered the "breadboard" effect? | | 01/01/70 00:00 |
| Inductance | | 01/01/70 00:00 |
| Hey! | | 01/01/70 00:00 |
| So what? | | 01/01/70 00:00 |
| specifically | | 01/01/70 00:00 |
| Let\'s not go overboard ... | | 01/01/70 00:00 |
| This does not make him learn to swim... | | 01/01/70 00:00 |
| I have only my own experience ... | | 01/01/70 00:00 |
| Not Atmel problem | | 01/01/70 00:00 |
| things change | | 01/01/70 00:00 |
| looking at the wrong characteristic | | 01/01/70 00:00 |
| OT: to Richard | | 01/01/70 00:00 |
| OT: I hadn\'t but I have ... Yes, I\'m interested! | | 01/01/70 00:00 |
| You are probably right | | 01/01/70 00:00 |
| do you have a 10-100nF directly across the | | 01/01/70 00:00 |
| *** PCB and schematic *** | | 01/01/70 00:00 |
| I cannot find C1 | | 01/01/70 00:00 |
| Ahh, it is the supercap! Needs some changes! | | 01/01/70 00:00 |
| Surprisingly It works like it is | | 01/01/70 00:00 |
No, no... | | 01/01/70 00:00 |
| I can't really 'read' your PCB but ... | | 01/01/70 00:00 |
| It is connected | | 01/01/70 00:00 |
| Is any old recipe. | | 01/01/70 00:00 |
