Re: [iPAQ] expansion pack Chip Select problem

"Hicks, Jamey" wrote:

> > -----Original Message-----
> > From: Vincent Nollet [mailto:vincent.nollet@imec.be]
> > Sent: Tuesday, January 29, 2002 5:30 AM
> > To: Hicks, Jamey
> > Cc: ipaq@handhelds.org
> > Subject: Re: [iPAQ] expansion pack Chip Select problem
> >
> >
> > "Hicks, Jamey" wrote:
> >
> > > 1) OPT_READY_L (Pin 57) of the extension pack connector
> > must be pulled
> > > low by the expansion pack to enable signals to be driven to the
> > > expansion pack
> > > 2) OPT_NVRAM_ON must be asserted
> > > 3) OPT_RESET must be deasserted
> > >
> > > Jamey
> > >
> > > > -----Original Message-----
> > > > From: Vincent Nollet [mailto:vincent.nollet@imec.be]
> > > > Sent: Monday, January 28, 2002 12:11 PM
> > > > To: ipaq@handhelds.org
> > > > Subject: [iPAQ] expansion pack Chip Select problem
> > > >
> > > >
> > > > Hello,
> > > >
> > > > We designed an expansion pack for the ipaq 3760. When
> > > > attaching a logic
> > > > analyser to the expansion slot,
> > > > we notice that the data passes correctly on the data bus.
> > The CS(Chip
> > > > Select), WE (write enable) and OE(Output Enable) pins,
> > > > however, do not
> > > > get low, as they should.
> > > > Probably we are missing something obvious: do we need to put
> > > > some of the
> > > > GPIO pin in some state when the sleeve driver is executed ?
> > > >
> > > > Can anybody give us a checklist of things we absolutely need to
> > > > set/reset whenever we want to address the expansion pack
> > in a correct
> > > > way.
> > > >
> > > > Vincent Nollet / Avasare Prabhat
> > > >
> >
> > Thanks for the feedback. One thing puzzles me though : when I
> > look in the
> > Ipaq h3000 Series Expansion Pack Developer Guide, I don't see I
> > "OPT_READY_L" signal (pin 57 == BATT_FLT).
> > Can you get back to me on that ?
> >
>
> Oh that's right. OPT_READY_L is my interpretation of that pin. If
> BATT_FLT/OPT_READY_L is high, then the buffers from the iPAQ to the
> expansion pack are disabled. This pin is pulled high from the iPAQ
> side, so the expansion pack has to pull it low to enable the other pin
> drivers.
>
> Jamey

I guess that there is a small error in the developers guide then !
On page 3-22 (Electrical interface), BATT_FLT pin has to be pulled up to
VDD by the expansion pack !
Furthermore, I can read on page 3-15 : " If an expansion pack does not
include a battery, it should not connect any of the battery signals
(...)"
Anyway, thank you, I will give it a try ...

Vincent Nollet
Received on Tue Jan 29 04:58:52 2002