mmc2 driver to connect beagleboard with external AD converter

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1

hi everybodyy

i intend to use the mmc2 pins on expansion header to connect directly
with an external ad converter. I looked all the mmc drivers at the
directory linux/driver/mmc, but i see that the drivers are just
written for mmc card. So can i use one of those drivers for my
purpose, or i have to drive my own driver ?

I'm a newbie with linux kernel and beagleboard, so i'm sorry if my
question is too silly.

Any pointers greatly appreciated.

Thanks

son dao

2

hi everybodyy

i intend to use the mmc2 pins on expansion header to connect directly
with an external ad converter. I looked all the mmc drivers at the
directory linux/driver/mmc, but i see that the drivers are just
written for mmc card. So can i use one of those drivers for my
purpose, or i have to drive my own driver ?

I'm assuming by "ad converter" you are referring to an analog to digital
converter. I don't know of any ADC which has an MMC interface. If you
have found one then yes, you'll almost certainly need to write your own
driver. Where is this ADC coming from?

I'm a newbie with linux kernel and beagleboard, so i'm sorry if my
question is too silly.

No worries.

Cheers,

- Ben

3

Hi Ben
Thanks for your answer.

The ADC is Texas Instrument ADS8422EVM. My purpose is connect 16 bits
ADC to the beagleboard through MMC2 port on expansion header. The MMC2
port on expansion header has 8 pins, so it can support parallel
connection and i want to take advantage from this ability to establish
a fast data transfer between beagleboard and ADC. I think we can
connect ADC directly to the MMC2 pins by using the cables (that means
we don't need an ADC with MMC interface). Am i right ?

Cheers

Son Dao

4

panzerde wrote:

Hi Ben
Thanks for your answer.

The ADC is Texas Instrument ADS8422EVM. My purpose is connect 16 bits
ADC to the beagleboard through MMC2 port on expansion header. The MMC2
port on expansion header has 8 pins, so it can support parallel
connection and i want to take advantage from this ability to establish
a fast data transfer between beagleboard and ADC. I think we can
connect ADC directly to the MMC2 pins by using the cables (that means
we don't need an ADC with MMC interface). Am i right ?

No. This AD converter is not MMC, it has a 8/16bit parallel interface
that you could interface to some GPIOs, but that is slow, read
the other threads about that.

5

GPIO as a memory bus? it is too slow.

2011/2/16 Vladimir Pantelic <vladoman@gmail.com>

6

Maxim Podbereznyy wrote:

GPIO as a memory bus? it is too slow.

well yes, that is what I said, no?

> ....
> that you could interface to some GPIOs, but that is *slow*, read
> the other threads about that.

:slight_smile: