M. Adam Davis escreveu: > On Fri, Nov 14, 2008 at 12:42 PM, Isaac Marino Bavaresco > wrote: > = >> This manufacturer did not said what was >> their controller supplier, just said it was "KS0108 compatible". >> >> After some work, I found that the controller does not honors the >> data-sheet timing: all bus transactions must be approx. 50% slower than >> that is stated in the data-sheet. >> >> After finding the solution I contacted the manufacturer and they said >> that there are indeed "minor" differences, but this is a new "feature", >> not a defect, and it has come to stay!!! >> >> Have anybody found such a problem before? >> = > > Sure. Every time a product is cost reduced (and, in general, you have > to cost reduce your parts every 2-5 years to stay competitive) you are > bound to have differences between the original and the cost reduced > version. It's unavoidable. > = I don't think this was due to cost reduction. I think they tried to make a clone of the original controller, ended with a bad set of masks for the silicon and didn't want to spend more money to make a new set (or they only found the error after they had made a zillion parts). > Reputable companies are generally very good at alerting customers in > advance of a product change, give them an opportunity to test the new > model, and an opportunity to make a last buy of the previous product > before discontinuing the old version. But you pay for that with more > expensive parts. > = They are selling the chips with the same specs as the Samsung parts (even some English errors are the same in both data-sheets). > Many companies offer poor service, and may not even alert their > customers of changes. In this case you're likely to get a much better > price, but that's the tradeoff. > > When possible, I design in and test with several different parts and > vendors so that there's no lock in. When a part is discontinued, or > doesn't work/meet specification I can quickly switch without a > redesign and review, and then take some time to reevaluate the parts > if needed. > > = This LCD module is sort of a commodity, several manufactures around the world make them almost exactly the same, with different clones of the KS0108. I already used parts from many different manufacturers and this was the first time I had problems. __________________________________________________ Fa=E7a liga=E7=F5es para outros computadores com o novo Yahoo! Messenger = http://br.beta.messenger.yahoo.com/ = -- = http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist