Looking for SPI to Ethernet solution

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There are plenty of RS232 to Ethernet converters out there from the big players but I'm looking for SPI to Ethernet in one shot.

Against my wishes the team took away my RS232 lines and gave me SPI only. I've found a few through google searches but they were all from no-name suppliers and for a project like this supply chain will kick that back in a hurry.

Anybody know of an SPI to Ethernet solution? Something like the Lantronix XPort but SPI instead.

Shannon

Go electric!
Happy electric car owner / builder

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Xport + Mega48?

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certainly workable but adds complexity to the system design. We'd have to task our software guys with writing and maintaining an extra set of code. I was hoping for a drop in solution like the Xport would be if it had an SPI interface.

Go electric!
Happy electric car owner / builder

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Check out microchip's ENC28J60 at:

http://www.microchip.com/wwwprod...

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Maybe I missed it but isn't that chip just a controller?. It doesn't have a tcp/ip stack or anything right?

Go electric!
Happy electric car owner / builder

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Right, no tcp/ip stack.

What you could do is to add a very small tiny AVR to convert between SPI and UART so you can put an UART to Ethernet module there.

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You asked for ethernet not tcp/ip! There's no reason why you can't just send MAC packets and have software on the other side to receive/send them, but it really does make things easier if you do use tcp/ip. This will chew up a bit of ram and code space though - depending on what bits you actually implement. Just doing UDP can simplify things.

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I'm currently using the WIZnet 5100 chip (WIZ811MJ module). It provides a TCP/IP stack and supports both SPI and direct bus interface.

See: http://www.wiznet.co.kr/en/index.php

Don

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THERE we go! Thanks Don. That is looking more like what we need.

I appreciate the suggestions to add another microprocessor to the product but it really is not feasible. If this was a little home project I would say no problem but in a commercial product that has to fit within the frame work of a project already well underway it just won't work. Someday when we have time for our software team to learn about TCP/IP and a new processor and a new tool set and new document release procedures and new manufacturing support procedures and.... THEN we can think about putting another processor in the product.

Go electric!
Happy electric car owner / builder

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Shannon,

While I can understand part of that argument is it not the case, for a commercially produced product, that BOM is the real driver? I'd go with whatever were the lowest cost solution (even if that involves amortising some development costs across a number of units). Having said that - the Wiznet unit does seem to offer a lot of $18 and I'll bet you could get a bulk discount if you approach Wiznet with a large enough order.

Cliff

PS That ENC28J60 from Microchip is just $3 and Microchip's AN833 seems to present a stack of TCP/IP software for a PIC microcontroller. I think this is one of those rare occasions I'd given in and use a PIC! (or maybe AN833 can be ported to AVR - maybe someone already has?)

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clawson wrote:
Having said that - the Wiznet unit does seem to offer a lot of $18 and I'll bet you could get a bulk discount if you approach Wiznet with a large enough order.
The WIZ811MJ module cost me US $16. The W5100 chip can be purchased for US $3.16 in single unit quantities.

I should mention that the W5100, even though it implements a TCP/IP stack, still requires a fair amount of ATmega software for the application and W5100 interface.

Don

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clawson wrote:
PS That ENC28J60 from Microchip is just $3 and Microchip's AN833 seems to present a stack of TCP/IP software for a PIC microcontroller. I think this is one of those rare occasions I'd given in and use a PIC! (or maybe AN833 can be ported to AVR - maybe someone already has?)
There are in fact several TCP/IP stacks for ENC28J60 + AVR.

Stealing Proteus doesn't make you an engineer.

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A M32/644 board with software & schematic

http://www.ulrichradig.de/home/i...

/Bingo

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clawson wrote:
Shannon,

While I can understand part of that argument is it not the case, for a commercially produced product, that BOM is the real driver?

I would say that in a lot of industries that is the case. However I design laser controllers and in our case we could virtually have a zero BOM cost for the electronics and it wouldn't budge to system cost very much. Those laser heads are expensive jewelry!

In my case complexity and infrastructure are big considerations. We have to think about the long haul when it comes to support in manufacturing, service and supply chain.

Shannon

Go electric!
Happy electric car owner / builder

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Shannon,

Having got interested in adding Ethernet to AVR because of this thread I have to say that the overall best (i.e. lowest cost ;-)) option really does seem to be the $16 WIZ811MJ/WIZ812MJ. With the ENC28J60 you'd be looking at adding a crystal and Magjack anyway and an "unknown" board layout of something that may be potentially noise sensitive.

I have to say that the thing that REALLY intrigues me (but no use for you I don't think) is that $30 buys you this:

http://www.ewiznet.com/goods_det...

That's a whole load of electronics for just $30. It's got all the bits of one of the $16 modules and then a mega128 with 8MHz crystal, a 32KB SRAM and an AT45 dataflash - you get all that for $14 extra.

Cliff

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Folks, be warned that Wiznet have just changed all the prices on their web site because of the $ weakening against the Korean Won.

http://ewiznet.com/notice_view_t...

So the $15.99 modules just became $19.99. Distributors (such as www.saelig.com ) may not have made the price adjustment to their current stock so NOW may be a good time to buy these modules if you intend to!

Cliff

BTW the 811/812 modules sell on the Korean website of Wiznet at 28,582 Won which is currently $22.96 - so the $19.99 prices is STILL a bargain! (at $15.99 they were actually selling for only 19,904 Won)