On 2010-08-07 01:11, Carl Denk wrote:
>
>> On 8/6/2010 12:02 PM, Bob Blick wrote:
>>
>>> Backlight draws too much current?
>>>
> Backlight not hooked up yet. Last error message I got was:
> "PK2Error0027:  Failed verify (Address =3D 0x0 - Expected Value 0xEFAE -
> Value Read 0x0)", which is different, previously got Vpp error, which in
> part says:
> PIC18F devices may require up to 10 uF of capacitance on the VDD pin to
> program properly.
>
> I have had the 10 uF, and made the changes to the MCLR and control
> line.I believe this is still pointing to the PGD and PGC lines, which I
> will attack next. The error goes away (as previously) when the LCD is
> disconnected.
>
> Per Olin's link, PGD should have 100 ohm to the programmer and a 47 -
> 100 pf to ground. The PGC should have a 47 pf. Originally I asked about
> resistor values on the pins going to the application, and these go to
> the programmer. Think I'll try Olin's way first.

What is "the application" in this case ? The LCD ?

Olins 100 ohm resistor and caps are (as far as I understand) mainly
for suppression of ringing on the lines. In most cases they are
not absolutely needed.

I would definitely look first at the RW line...



>
> I do have a WIRZ-OEM RS-232 to LCD board. The LCD works OK with it.
--=20
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