CF card and the Sharp PC3000/HP95LX experiences (fwd)

[Sven Utcke <utcke@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx>]

Hi all,

> From: FELIQUE CHRISTIAN <Christian.Felique@xxxxxxxxxx>

reported the following with regard to his HP95LX --- maybe this is of
some interest to you, or maybe you could help out with some of his
questions:

> I read about your CF experiment for the Sharp PC3000, and was keen to try it on
> my HP95LX. This is what my experience is with a Sandisk CF 32Mb card:
> 
> (1) In the HP95LX the CF still draws current even when it is turned off.
> (2) When reading/writing to the card annoying black lines appear on the screen.
> 
> (1) I solved this by cutting the Vcc line inside the PCMCIA to CF
>     adapter, on the PCMCIA side of the adapter. Note that there are
>     three voltage lines on a PCMCIA connector: Vpp1,Vpp2,Vcc. Vpp1
>     and Vpp2 are (at least I think so) connected to the Vcc of the
>     CF slot. The CF slot only has Vcc, and no Vpp1 and Vpp2. I think
>     that Vcc on the PCMCIA connector is always powered, and Vpp1 and
>     Vpp1 is only powered when reading, writing to the card.  Anyway,
>     the CF card still works, and the card doesn't draw current
>     anymore when my 95LX is turned off.
> 
> If you experience the same problem on your Sharp, then this might be a solution
> for you too. 
> 
> (2) The reason for this problem is the fact that the CF drains a lot of current when
> reading/writing. The LCD screen is connected to the same 5V power supply as the PCMCIA slot.
> That explains the black lines.
> 
> My questions:
> 
> Do you know how much current a CF drains when reading/writing ?  Do
> you experience the same problems on your Sharp PC3100 ?  Are there
> members of your mailing list that experienced this problems, and/or
> found any solution for it. Maybe other soldering/cutting lines/CF
> adapter modifications would solve this problem ? Any advise is
> welcome.
> 
> Thank You
> 
> Best Regards,
> 
> Christian Felique
> 
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