I've got a successful project operating using an MSP430F148 talking
SPI to a flash card. The problem, however, is as follows:

The prototype of the project has the flash card mounted very, very
near the MSP430 (i.e. the MSP430 is sitting directly underneath the
hollow part of the SD card socket), and it works great.

On the device this gets installed in, however, the card needs to be
accessible at a point at the other end of the board, about 4 inches
worth of PCB traces away.

Here's the problem: The card, when inserted in the scoket right over
the MSP430 works great. When inserted in the other socket a short
distance away, doesn't work at all. The timing gets all hung up and
broken.

I have tried different types of pullup resistors on both ends, but to
no avail. There are 1 uF bypass caps installed near the cards, and
currently a pulldown on the \CS pin and SOMI and SIMO. The presence or
lack thereof of resistors don't seem to matter.

Why is it that I have heard of some people putting 3 meter long SPI
dongles with no termination or pullups, and I can't get it to work
three inches from the card?

Once again: The card works when near the MSP430, but not when it is
installed about 4 inches away.

I thank you very much for your assistance..

Cheers and good day,

Greg Linder

FWIW, I've got an SD card (SPI interface) in a socket located
approximately 12" from an MSP430 and with 4 connectors inbetween to
work just fine. This is on a Dev Board setup. In production, the SD
socket is on the other side of a 6-layer PCB, and is only around 1-2"
from the MSP430.

One thing I did notice was that the code I tried initially ran the
card at a very high SPI clock speed, and the signals at the SD card
looked awful. I brang the speed down and now it looks and works fine.

--Andrew

One thing I did notice is that the signal quality at the 

--- In msp430@msp4..., "greg.linder" <greg.linder@...> wrote:
>
> I've got a successful project operating using an MSP430F148 talking
> SPI to a flash card. The problem, however, is as follows:
> 
> The prototype of the project has the flash card mounted very, very
> near the MSP430 (i.e. the MSP430 is sitting directly underneath the
> hollow part of the SD card socket), and it works great.
> 
> On the device this gets installed in, however, the card needs to be
> accessible at a point at the other end of the board, about 4 inches
> worth of PCB traces away.
> 
> Here's the problem: The card, when inserted in the scoket right over
> the MSP430 works great. When inserted in the other socket a short
> distance away, doesn't work at all. The timing gets all hung up and
> broken.
> 
> I have tried different types of pullup resistors on both ends, but to
> no avail. There are 1 uF bypass caps installed near the cards, and
> currently a pulldown on the \CS pin and SOMI and SIMO. The presence or
> lack thereof of resistors don't seem to matter.
> 
> Why is it that I have heard of some people putting 3 meter long SPI
> dongles with no termination or pullups, and I can't get it to work
> three inches from the card?
> 
> Once again: The card works when near the MSP430, but not when it is
> installed about 4 inches away.
> 
> I thank you very much for your assistance..
> 
> Cheers and good day,
> 
> Greg Linder
>