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Subject: Re: humongous lcds

Re: humongous lcds

From: ian douglas <>
Date: Thu, 17 Nov 2005 15:16:02 -0800

Liberman Shachar wrote:
> if you think there was
> a way to make a bigger remote screen work with the unit

By simply pulling some wires and splicing onto the existing circuitry,
I'd guess no. Again, the pins, wires and voltages needed to drive any
other screen will almost certainly be completely different than what's
in place to draw pixels on the existing screen. You would need something
in between (more than just wires) that understands what input signals
correspond to a drawing a particular pixel, and translate it to send
voltages to the appropriate pins at the appropriate voltage for the
appropriate length of time to draw one or more pixels on the bigger screen.

If by change you find a bigger screen that uses the exact same graphics
instruction set that your H100 has, then you'll be one step closer, but
then you'll still need to worry about your next point:

> if threading 16 pixels to one result in over resistance of the unit
> and making it explode.

Yes, there's the likelihood that the output voltage of the H100 graphics
controller will not be sufficient, or perhaps too sufficient, to drive
the input pins on the new graphics controller too. You certainly
wouldn't want to draw on both screens at the same time, regardless if
the new graphics controller happens to be identical to the one in your
H100 - otherwise you're increasing the load (resistance) on the circuit,
and an increase in resistance means a drop in current at the same
voltage, which may impact other circuits on the board ... you probably
know all that already.

One idea: if your H100 has some kind of output port, like a "remote"
that has a smaller LCD screen on it, maybe look at how the data is being
sent back and forth to that screen (scopes and analyzers work great for
capturing data signals like that), such as a signal that specifies "a
remote has been plugged in" and signals back like the artist name, song
title, etc., and use those as input/output signals to a totally
different circuit that manages the bigger screen and use the input
signals to let the new circuitry (microcontroller, flash memory, RAM,
etc) know what to write on the bigger screen. But developing a new board
to do all of that will cost hundreds of dollars I imagine?

Ian Douglas
blogs & photos:
Received on 2005-11-18

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