Anyone can help on GPACON/GPADAT issue?

Gianluca Renzi gianlucarenzi at
Fri Apr 17 10:03:17 CEST 2009

On Thursday 16 April 2009 18:03:22 Ben Dooks wrote:
> On Thu, Apr 16, 2009 at 05:43:18PM +0200, Gianluca Renzi wrote:
> > Hello list,
> > I would like to know if there is something wrong in my setup.
> > I have a custom board s3c2442BL based.
> > I ported some test points into a strip just to have an "expansion
> > connector". Those pins are GPA12..GPA16. On reset they are at 1.8V is it
> > normal? If I configure them as OUTPUT in GPACON register and write the
> > corresponding bit High its level remains 1.8V not 3.3V. Is it normal? It
> > looks like it has some PULLDOWN register enabled, but the GPIO A is the
> > only port that *DOES NOT HAVE* such register (from port B to port J they
> > have PD regs...) They are wired DIRECTLY from CPU pins to strip pins. No
> > pullup, pulldown or whatever...
> are you sure these pins are referenced to VDDio, and not VDDmem?
Yep. You are right. On page 261 on User's Manual it is written:
(Note) The GPA21 Power is depend on VDDOP, the other pads(GPA0~20, GPA22~24) 
are all on VDDMOP.
Where VDDOP means +3.3V and VDDMOP means +1.8V.

That clarify everything.

Thanlks to all.

Best regards,
Gianluca Renzi
phone: +39.0542.609120
fax: +39.0542.609212

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