Outlet for old datasheets

[Darshevo]

Here is another piece grabbed at the ecycle joint.

The little 14 pin dip on the bottom is a TI first row 3495 Z NK second row SN7406N.

Obviously a homemade item (its even about 3/4 wire wrapped). In this case rather than have one of the resident experts tell me what this little jewel does, I would actually like a good lead on old datasheets. I looked up the SMC and the TI on alldatasheet and datasheet archive and came away empty handed. Not to say they aren't there, I just don't seem to be able to find it. Once I have datasheets in hand I should be able to decipher what it does. Or at least make a n educated guess, time to start learning

-Lance

 

[Chuck(G)]

:headslap: Google is your friend.

Suppose that I wanted to figure out what that SMC chip is. Well, the first thing I'd do is discard any alpha suffixes (I can always put them back) and maybe alpha prefixes (same rule) and then search for that plus the word datasheet.

If I get too many hits, I start adding things back, like the manufacturer SMC. So try searching for "91c92 datasheet SMC" and see what you get.

Sometimes if the chip is fairly old, I can find it in a catalog on bitsavers. If that fails, I go to my own bookshelf full of disintegrating databooks. If I'm really desperate, I'll also check my file of old datasheets (many on slowly disappearing thermal fax paper).

 

[channelmaniac]

When you see SMC, think networking and you'll most likely be right...

My guess was a 10BaseT network adapter considering the smaller PE-68819 transformer.

http://www.datasheetarchive.com says it's an ISA bus single chip ethernet controller with RAM which confirmed my guess.

SMC makes a LOT of networking devices and has for years. Hubs, switches, NICs, wireless adapters/routers/access points, and broadband routers/firewalls.

RJ

 

[Ole Juul]

(its even about 3/4 wire wrapped)

Where's the wirewrap?

 

[krebizfan]

Well, google pops up information on the sn7406n real quick and the SMC chip is referred to often enough. The ports on the board give it away.

What I would interested in is what's on the other side of the board. I would like to know what type of computer this prototype board is intended to work with.

 

[Chuck(G)]

It's also sometimes useful to know what manufacturers have morphed into--SMC->SMSC. And SMC made support chip sets for a long time (e.g. floppy controllers, USARTs, "Super I/O", etc.)

Given that the 91C92 is an ISA-bus interface ethernet controller, this might be intended for an x86-type system, but my guess is that the SMC chip is simply being used as a 10-base-2 to 10-base-T bridge, with the LEDs showing status (hence the 7406 driver used as a driver for the LEDs). That black rectangular lump to the left of the SMC chip should be a crystal or an XCO, if I'm guessing right.

Mind you, this is just a guess.

 

[Darshevo]

Thanks for the tip on stripping down the part number, I got back much more usable results - when using the whole part number it was either dead links or websites that wanted me to submit a request to buy

Knowing what the numbers on the chip mean is 1/2 the battle

I had a suspicion that the blob on the left was a crystal. Marked 20.000m. My guess was that that mean 20 mhz?

Here is a picture of the wire wrapped side

Just think, someday I will have a working knowledge of this stuff and you will have to find a new newbie to teach :D

-Lance

 

[Chuck(G)]

Now that I see the connector on the opposite side, without tracing wires, it looks a lot like a PC104 setup.

 

[analog]

Yep, looks like a homebrew PC/104 ethernet card.