Chaipi Wijnbergen wrote: >> I have two types of LCD modules, each is 14 pin, 2 lines of 16 >> characters. >> It looks like one type has VCC, GND in pins 1 & 2. >> And the other type has VCC, GND in pins 13 & 14. >> What is the difference between those two modules? are they software >> compatible? Paul B. Webster wrote: > It's ridiculously obvious, but perfectly true, that in the case of the >second unit, someone has numbered it in reverse. Whether by malicious >intent or mere foolishness is hard to figure. > > Just make sure you know which is ground (on most PCBs, ground is the >largest area of copper) and which Vcc, check that the "contrast" >connection goes to the resistor chain, and all the other connections >(which won't be damaged anyway if mis-wired as they are all in effect, >inputs most of the time) will presumably follow the pattern. > > If you don't have the datasheet reference, we can find it. Of course, >Hitachi went and *moved* it a while back, demonstrating the "modern" >preference for form over functionality, but .... that's life! NOT so obvious ! I have just been through this with some Seiko 2x16 units. Would you believe the different pinouts are not just reversed - quite different. For example, the Vcc & Vss pins are reversed - a recipe for disaster ! Also, the Seiko site has the WRONG datasheet for the L1672 series. I found what I think is the right one on the (Australian) Avnet site. Before the Seiko saga I also used to think they were all much the same. I normally use the Powertip devices but I needed the Seiko to fit in a 1RU box. Geez, just when you thought a LCD was a LCD... Regards...