WinTest Demo

pgs1333

New member
I seem to be having difficulty running the CFAG12232D_WinTest demo program.

I have checked the wiring and it looks good. I have it connected to the parallel port and i do have the backlight ON.

the voltages are all at there recommended, VDD=5V, Vo=4.7.

What are the steps to show, say, the V-Stripes? and do i need VC++ installed to run everything?

any help is appreciated
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CF Tech

Administrator
Did you load "port95nt"?



Once that is loaded, if it still does not work, you might try changing the port modes in your BIOS (EPP, SPP, ECP etc).
 

pgs1333

New member
i did install 'port95nt'.

When i run WinTest, the program opens but nothing happens when i press any of the buttons.

I am running winXP Pro, how would i change the port modes?

And i am running the CFAG12232 demo, not the CFAH display that was posted, should i be?

thanks
 

CF Tech

Administrator
> i did install 'port95nt'.

OK

>When i run WinTest, the program opens
>but nothing happens when i press any
>of the buttons.

Probably your wiring.

>I am running winXP Pro, how would i
>change the port modes?

BIOS Setup (probably not what is wrong)

>And i am running the CFAG12232 demo,
>not the CFAH display that was posted,
>should i be?

CFAG12232 demo is the right program once your wiring is correct.

CFAH_WinTest, in combination with a cheap multi-meter is pretty useful for debugging your wiring. You can control the lines individually with CFAH_WinTest, and check that the right pins on the LCD move with the meter.

Did I mention that it is probably your wiring ?
 
pgs1333 said:
the voltages are all at there recommended, VDD=5V, Vo=4.7.
Actually, Vo is specified as Vdd-Vo = 4.7, so the actual voltage should be around 0.3 volts. A useful range might be +2v to -5v, referred to ground. The diagram in the data sheet is misdrawn, the pot should go from +5v to ground, with the wiper to Vo. With +4.7v on Vo, there is probably insufficient contrast to see any pixels on the display. Try grounding Vo, for a quick check.
 

pgs1333

New member
Thats what I found out this morning, there was 10k pot installed on my prototype instead of the 10k-20k i asked for. As soon as i grounded it, i did get half of the display to work.

LCD Pin 6 is not being toggled by the software though, so i do not get output on that side of the LCD. I know ths LCD still functions because i connected LCD Pin 6 and 7 and was able to display the other half of the display on it.

I am running WinXP Pro and when I do run the CFAH_WinTest to debug the circuit, i noticed that LPT Pin 14, which connects to LCD Pin 6, does not toggle. LCD Pin 6 stays at logic low, so it must be software issue.

Has anyone seen/heard of this occuring before?
 
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