Elizabeth Simon

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elizabethsimon

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    • "I'd be more surprised to hear that the debug\/release problem had gone away. Even something as simple as blinking an LED can change the timing sufficiently to cause problems to disappear or change their nature in unpredictable ways.\n\nSounds like you encountered a case where the compiler optimized out some critical bit of code (but only in the release version). Very frustrating when that happens. One reason you can't have too many debugging tricks to call on..."

    • "I remember a large portion of this history (have I really been at this that long). One of the biggest problems with many of the debugging techniques mentioned is that they require substitution (modification) of either hardware (ICE) or software (debug code). Sometimes the system would fail ONLY in the original configuration or the failure would be different when set up for debug.\n\nAlso, does anyone else remember the ROMulator? Useful for replacing an EPROM if\/when the ICE was not available."

    • "What I want is a robot that performs ALL household cleaning tasks. Up to and including finding places to store the various bits of incomplete projects (and retrieving them on command when I have a spare hour to work on them).\n\nAnd at the moment, the ability to take photos of old equipment and properly identify and price it for sale would be really valuable. last Saturday I helped some friends pick up equipment from the estate of a ham operator who had passed away. I've been sorting and taking pictures ever since. Granted that much of what I ended up with will be sold by the bag or box, there are a few items that need to be better categorized. For instance there is a box of analog meters of sizes and types that needs to be looked at..."

    • "It was mostly a happy coincidence. Depending on the relay\/solenoid, a 3.3V supply could work well to maintain a 5V coil drive. With the proliferation of voltages required in systems now, it's increasingly likely that you might already have a suitable supply."

    • "I've used a variation in a relay circuit that uses two supply voltages, an RC and a diode. If you put the RC between the higher supply voltage and the relay and the diode between the relay and the lower supply voltage then when you activate the coil, it behaves as the circuit in 2b up to the point where the lower voltage supply starts sourcing current through the diode.\n\nOf course, you do still have to pay attention to all relevant specifications etc. "

    • "@Ull \"...Installing in fractions of 1 U will always be a problem - irrespective of any pattern that's repeating with a period of 1 U :)\"\n\nWhy then is the rack NOT marked with 1 U lines so that I can tell when the equipment is lined up. This would be really handy when I'm balancing the equipment in one hand while trying to get a screw through the flange into the rack with the other. Fortunately, I've got the rack filled up enough now that it's not normally a problem :)"

    • "I remember looking at a history of such things not long ago. I remember reading that there was also a 21\" (or some such) rack standard.\n\nI think the 19\" standard came from the telephone industry although it could have been the electric power industry. Somewhere along the line they got together and started using the same size racks.\n\nI'm not sure where the unit height came from though...\n\nNow for another bit of trivia. Did you know that the hole spacing on the racks is NOT uniform? There are three equally spaced holes per unit but the spacing between the last hole of one unit and the first hole of the next unit is a bit different. This can be really frustrating if you are installing equipment in a rack and for some reason you want to start in the middle instead of the top or bottom. If you happen to install the first unit 1\/2 U off you will find that you reach a point where the screw holes don't line up (usually on the third or fourth box that needs to be installed."

    • "Mockingbirds also have the same ability. When I was living in the city, there was one who could do a credible imitation of a really annoying car alarm.\n\nThis whole thing is very disturbing. I think I'll stick with physical keys for physical locks... And I guess I'll have to continue to live with remembering passwords. My solution to that is a program called KeePass. All passwords are stored on MY devices and I only have to remember a couple..."

    • "I seem to remember a sci-fi story about a computer that simply refused to work until the operator said please."

    • "Their spec sheet mentions SETP and IGES mechanical models but no info on where to get them. And no mention of what the pinout is on the headers so you can wire it up...\n\nIt does look like a useful product for this purpose though."