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. 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. 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. Typically, for complex products such as LCDs, I'll ask for a working code example and even development board and store it for later use. When I encounter problems, I'll take out the design board and test against their example implementation and code. If it still doesn't work, then I'll have them troubleshoot their LCD, code, and development board so they can give me a list of changes that need to be made to make it work. If the dev board does work, then I look at the differences between their implementation and mine. But, if I've done my job correctly, I can switch to another manufacturer and product if the changes make the current product unusable. But yes, this is not uncommon, and you need to plan for it in the design process. When you cost-reduce your products, please be kind to your customers and alert them. What goes around comes around... -Adam -- Please rate and vote for my contest entry: http://mypic32.com/web/guest/profiles?profileID=50331 -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist