Important features to have on 18F4620 Board?

[Mike, K8LH]

3v0,

Hook the LCD backlight Anode to VCC and put the backlight Cathode on the unused connector pin where I can drive it with a sinking PWM signal and that adapter would be perfect...

I have a similar manufactured adapter but they hard-wired the backlight to power pins (with appropriate dropping resistor) and the R/W pin to ground. It's got two unused pins on the 2x5 connector but I can't cut the backlight and R/W connections because they're buried. Bummer!

Mike

[3v0]

Changed as requested. Also made the board a bit easier to etch and solder. The pdf fils is a foil pattern that can be printed and etched. The zip file contains the Eagle sch and brd files.

[Mike, K8LH]

3v0,

Very nice. "Perfect" does indeed apply. I'll take two (grin).

I meant to edit my post to say it would be nice to have the backlight cathode available on the connector so that I could drive it with PWM or ground it but I couldn't edit my post.

btw, I wouldn't be opposed to a installing a couple jumpers if those small traces between pads is a problem...

Mike

[3v0]

Originally Posted by Mike, K8LH

3v0,

Very nice. "Perfect" does indeed apply. I'll take two (grin).

I meant to edit my post to say it would be nice to have the backlight cathode available on the connector so that I could drive it with PWM or ground it but I couldn't edit my post.

btw, I wouldn't be opposed to a installing a couple jumpers if those small traces between pads is a problem...

Mike

Are you saying you want the anode hard wired to +5 and the cathod to the connector pin. As in I have is bas awakards? If you think I still do not understand mark up the schematic using a paint program.

The lines between traces should not be a problem with a decent setup. The thin lines here are .012 and I have used .001. The .012 is quite dependable but the .001 traces need to be verfied after etching. Most of the time they are good.

[Mike, K8LH]

Yes, backlight anode to VCC and cathode to the connector. Sorry I didn't notice it in your first updated drawing.

Mike

[3v0]

LCD backlight cathod is now connected to the 2x5 and the annode to +5.
The pdf fils is a foil pattern that can be printed and etched. The zip file contains the Eagle sch and brd files.

[Mike, K8LH]

3v0,

Bravo! That looks very neat and clean.

Mike

[Pommie]

Just out of curiosity, what is the purpose of the pullup on RS?

Also, would a pull down on RW make sense for code that uses delays rather than checking the busy flag.

Mike.

[3v0]

Originally Posted by Pommie

Just out of curiosity, what is the purpose of the pullup on RS?

It has been a while. I think the pullup on RS is there because it connected to A4 (open collector output) on the original application. In general it makes more sense to place that pullup on the target. That way the pullup will be there regardless of how the signals are brought out to the connector.

Also, would a pull down on RW make sense for code that uses delays rather than checking the busy flag.
Mike.

Yes. There is room of it between the pot and the LCD connector.

Also the contrast resistor(s) may be muffed up or at least simplified. The documentation I am looking at shows a single variable resistor between pin 3 and GND. I have the pot wired up as a voltage divider splitting VCC and GND.