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The Kill A Watt LCD driver

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evios

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kill a watt serial interface

Hi all the experts here:

Basically I was having my project. But then I need the data from a device called Kill A Watt. Before it has been drived to the output, there are 6 connections to the LCD driver as shown below:
3061805595_8cb0eaa264.jpg


The LCD seems to have 20 pins configuration:
3061805971_3eddf5c317.jpg


Can anyone advice me for that? Because I really need it for the project. Thanks.

Any references are welcomed too.

Thanks
 

Iouri

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1-wire kill a watt

Some LCD has serial interface that's why you have 6 wire ribbon cable, 20 pins it is COG(chip on glass) display, so your PCB can drive two different types of the display
 

GrandAlf

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lcd driver 6 wire

If it is a standard alphanumeric display you need 6 wires to use in 4 bit mode. Cannot really tell from your photos whether Alpha or Graphic.

You need
D4-D7 4 wires
E 1 Wire
RS 1 Wire

Connect WR to ground (write mode)

Power of course
And I think CON connects to ground for darkest display, really needs around 10k pot across power, with centre to CON

Not sure of connections if its a graphic display.
 

evios

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configure kill a watt

Thanks for the replies!!!
But what is meant by these pins anyway?
D4-D7
E 1
RS 1

Sorry I just found it a bit complicated. Thanks again.
 

GrandAlf

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kill a watt setup

D4-D7 are data lines Leave D0-D3 unconnected
E = Display Enable
RS = Display Reset
As you are probably only writing to the display, you should connect W/R to 0V
Apart from power and contrast, these 6 lines are all the data connections you need for 4bit operation. Always assuming that this is an Alphanumeric display, and your software is setup to operate in 4 bit mode. If this is a graphics display, the the above will not apply, there are different sorts.
 

evios

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lcd graphics display chip on ribbon cable

Well thanks for the reply...
main_p4400.jpg


I think this is more like Alphanumeric display.
I just want to get the reading out and input into PIC
 

GrandAlf

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This is a custom display, just for this meter. What I have said before is not relevant to this.
Sorry no idea how you would extract data from this unit. Its my guess that the display is a serial device.
 

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