Are there no capes which provide just I/O buffering and level conversion?

I've looked through the capes advertised on beagleboard.org but I
can't find anything that offers general purpose buffering and level
conversion. Is there really nothing of this sort available or am I
missing something?

Given the sensitivity/vulnerability of the BBB's I/O I would hae
thought an I/O cape that provides, say, 16 bidirectional 5v digital
I/O pins would be very useful. If it also buffered the A2D inputs
that would be a bonus.

I guess I'll have to DIY it on a breadboard cape.

How about this one?

https://www.kickstarter.com/projects/land-boards/33v-5v-gvs-cape-for-the-beaglebone

What about this one?

https://drive.google.com/file/d/0B6b4Rx-uVkeMMkotOThYdFVSMGM/edit?usp=sharing

Well it's OK except that they haven't actually produced it yet! :slight_smile:

... and *please* don't mail me as well as the list.

Nice picture! :slight_smile:

http://elinux.org/BBB-GVS

I’ve looked through the capes advertised on beagleboard.org but I
can’t find anything that offers general purpose buffering and level
conversion. Is there really nothing of this sort available or am I
missing something?

Given the sensitivity/vulnerability of the BBB’s I/O I would hae
thought an I/O cape that provides, say, 16 bidirectional 5v digital
I/O pins would be very useful. If it also buffered the A2D inputs
that would be a bonus.

I guess I’ll have to DIY it on a breadboard cape.

It is such a simple thing to make. Here is what you need:

http://www.digikey.com/product-detail/en/8100-SMT10/438-1032-ND/569736

For bidirectional push pull
http://www.ti.com/product/txb0108?keyMatch=txb0108&tisearch=Search-EN

For bidirectional open collector such as I2C
http://www.ti.com/product/TXS0108E?keyMatch=txs0108&tisearch=Search-EN

Make sure you order the correct packaging to match the board pitch above, or buy a different board with a different pitch.

Then on eBay I found these jumpers which work great. I ordered both male to female and female to female jumpers.

http://www.ebay.com/sch/i.html?_from=R40&_trksid=p2050601.m570.l1313.TR0.TRC0.H0.X200pcs+10cm+2.54mm&_nkw=200pcs+10cm+2.54mm&_sacat=0

I created a board with two of each, with enable pull up resistors and decoupling capacitors under the board. I have attached a picture.

Regards,
John

DSCN2720.jpg

Well, Chris, I am the “they” (it’s my kickstarter). I’ve got ten of them on my bench right now. And the board is listed at the end of the capes page. Regardless of the outcome of the kickstarter I am going to be selling them starting in a week and a half from now. I just wanted a way to get the word out there and if I got enough orders I could get a qty price break on the pricey voltage translation chips.

I am interested in any constructive comments on the technical aspects of the board.

Sorry for the email. I didn’t deliberately mail you as well as the list. I guess it’s because the CC Original author button was automatically selected when I hit reply and I didn’t deselect you. I did deselect you this time. Now if you set it to let you know when someone posts in this thread, there’s nothing I can do to keep you from getting an email. If I am wrong about how that works someone please let me know.

– Doug

[-- text/plain, encoding 7bit, charset: UTF-8, 26 lines --]

Well, Chris, I am the "they" (it's my kickstarter). I've got ten of them on
my bench right now. And the board *is *listed at the end of the capes page.
Regardless of the outcome of the kickstarter I am going to be selling them
starting in a week and a half from now. I just wanted a way to get the word
out there and if I got enough orders I could get a qty price break on the
pricey voltage translation chips.

Yes, sorry, I didn't put two and two together and realise that you
were the developer of the board.

I am interested in any constructive comments on the technical aspects of
the board.

I'd like more buffered/5v connections than you're providing at the
moment.

Sorry for the email. I didn't deliberately mail you as well as the list. I
guess it's because the CC Original author button was automatically selected
when I hit reply and I didn't deselect you. I did deselect you this time.
Now if you set it to let you know when someone posts in this thread,
there's nothing I can do to keep you from getting an email. If I am wrong
about how that works someone please let me know.

I think it may be down to how the list works. If you reply with
'Reply to all' then the sender *and* the list will get your reply.
Some lists filter this out so only the list gets the reply if there
appear to be two E-Mail destinations.

The ideal is a mail program with a specific 'Reply to List' command
which is different from 'Reply to all' and 'Reply to sender' but
there's only a few with this ability.

I can’t tell from the picture which board this is.
Do you have any product or contact info?
Thanks

For bidirectional push pull

http://www.ti.com/product/txb0108?keyMatch=txb0108&tisearch=Search-EN

Note the txb0108 has a low dc drive strength. They can’t pull a bus low if it has strong pullups.