Isn't a LOW logic signal always some magnitude above zero volts? Maybe 200 - 300 mv or so. In some cases higher. The spec for TTL, IIRC, for a logic low is <.8V, and a high is >2.2V or 2.4V, I can't remember for sure. For CMOS I believe it is .2Vdd and ..8Vdd respectively. So running a COMS device from 5V, a low would be < 1.0V and a high would be >4.0V. With this said, as long as the levels you're seeing as a logic low fit these criteria, then all should be okay. However, if they wind up in the undefined area between these levels, that may be where your problem lies. And that is that the levels are being interpreted incorrectly, therefore, it doesn't work. If this is the case, maybe you have a bad ground somewhere. Or maybe you just happened to get=20 a bad display. =20 Regards, Jim > -------- Original Message -------- > Subject: Re: [EE] DOGM LCD > From: IVP > Date: Mon, April 04, 2011 7:08 am > To: "Microcontroller discussion list - Public." >=20 >=20 > > Are the code examples (although for 8051 type architectures) of no > > help on their download page? >=20 > Nope >=20 > Most perplexing >=20 > I saw comments about problems with the Busy Flag, and did notice > some oddness myself. Sometimes BF cleared, sometimes not. At the > moment the D7 line goes low but not quite to 0V. That's using 1ms > delays rather than the polling scheme EA suggest >=20 > As I said, fiddle around enough and something usually happens to > get the ball rolling, but this LCD's putting up a fight >=20 > Joe > --=20 > http://www.piclist.com PIC/SX FAQ & list archive > View/change your membership options at > http://mailman.mit.edu/mailman/listinfo/piclist --=20 http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .