Syridian wrote:
Reset is sometimes connected via that RC network to provide a proper reset during power cycling. When power is first applied to the circuit, the Capacitor holds the reset pin low until it charges. This ensures that all signals are sable when reset is disengaged.
I can see that now.. But according to the datasheet I need to use the following power-up configuration:
![Image](http://img.villagephotos.com/p/2005-1/931454/timing.GIF)
The way I see it I can realize this by doing this:
![Image](http://img.villagephotos.com/p/2005-1/931454/reset.GIF)
And the delay for the INH pin during power up is set by a 80k resistor and 1uF capacitor..
But is it necessary with all these timing circuits.. I don't see it in all the other schematics found on this page..
Syridian wrote:
Personally, I would use a pot to adjust the contrast instead of your fixed resistors.
Will do that.. The Vo is the contrast adjustment pin right?
In the datasheet Vo is described as adjustment terminal for liquid crystal driving voltage so I'm a bit confused..
Syridian wrote:
The things I noticed are the resistors instead of potentiometer for the contrast adjustment and the connections to the INH signal. Why do have 3.3V at the input to the flip flop ? Also what are your plans with the flip flop ?
The voltage has been changed to 5V. I've connected the flip flop in order to use a push button to control if the LCD is on or off..
I'm going to use diba's COM-port winamp control:
http://diba.hotbox.ru/comctrl/
..so by using the flip flop I am able to use the same push buttons for powering the LCD on and off as I am going to use for the winamp control..
And I think it looks better with a push button rather that a switch..
I am going to use the MAX749 to create the -24 volts.. I suppose that's ok.
The datasheet for the MAX749 can be found here:
http://www.maxim-ic.com/quick_view2.cfm/qv_pk/1163