4x40 lcd 3rd/4th line problems


New member
Hey guys, I am experiencing a bit of a problem with my MTC-40400x 4x40 lcd. I ran it through the lpt port and was very happy that I got the test signal...or I got the module to actually power on and the contrast control showed all the blocks to be there.

When I put data into the top two lines it came up, but not in the lower two lines. I have since then used a multimeter to test the connection of the E2 line (*connected to lpt pin 14), it showed no resistence. I've tried the alternate addressing option on smartie...nothing. I have run out of ideas and want to know what you think.
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CF Tech

You are on the right track. Try switching the E1 and E2 lines. Then the top two lines of content should appear on the bottom line of the display.

If that works then it is definitely E2 not connected right, or not driven right by the software.

If the bottom two lines of content appear on the top two lines of the display, then the display is bad.

(This is the right forum, since it is not a CF display. ;) )