Re: CF memory card vs CF wireless card

On Tue, Dec 23, 2003 at 11:06:50PM -0800, Sriram Neelakandan Iyer wrote:
> 
> I have an ARM7TDMI based chip that has an on board CF controller. I
> have coded the Linux Socket Service Layer based on the SA11xx stuff.
> 
> I am able to read the CIS of a CF memory card properly. dump_cis
> prints the details as per the specs I use a SanDisk 64MB SDCFB card
> and i get the full CIS as per the data sheet properly.
> 
> But when i plugin a CF wireless card, the card detection happens,
> but dump_cis complains "no CIS present" .. i found that the
> Attribute memory was giving out randomly alternating values of 0x00
> & 0xFF.

What does "randomly alternating" mean exactly?

> 1. Is there anything special to be done to handle CF
> Wireless card (i.e. CF+ cards) to read the CIS space ?

All cards should behave the same in regards to reading the CIS; this
is done when the cards are operating in "memory mode" (as opposed to
"memory and IO mode").

> 2. Is there any init sequence to be followed for CF+ card power up ?

It should be the same init sequence that the pcmcia drivers use for
all cards, nothing special.

The only things that jump to mind, are to verify that your socket
driver is setting memory timings correctly.  The pcmcia-core code
should handle power-up sequencing (enabling the reset signal, applying
power, disabling reset, and enabling output from the card).

How did you come to observe the difference in reset behavior for your
two cards, exactly?

-- Dave


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