Recommended Ethernet MAC/PHY?

If staying with AVR was a done deal then my top choice for grafting ethernet to the AVR was the Microchip ENC28J60. First I heard it was to ship in July, then August.

currently lists September 15.

ENC28J60 has a lot of advantages, all on paper because the part isn't shipping. Small pin count. Easy SPI interface. Reasonable price. And will one day be available from every source currently selling PICs.

As you point out, running 10/100 let's you auto-negotiate the speed, making your product more compatible. You'll encounter some environments that require 100Mbps connections, even if the device doesn't call for it. It also avoids problems with duplex mis-match, which causes unreliable connections. (Negotiating to full-duplex yields a higher-performance connection too, though not a concern for you.)

Look at the ASIX AX88796l 10/100 ISA chip. It uses a modified NE2000 driver (like the Realtek RTL8019AS). You can source proto boards from

(you'll find Mega128 drivers for the ASIX there too).

You can buy in small quantities direct from the manufacturer ($175 for

25x, +$30 S&H and ~$45 T&T fee [wire transfer fee charged by your bank]).

However, it's QFP-128 footprint (slightly wider than the Mega128), it should run in 8-bit mode (but I haven't tried it); and it requires 5 address lines, 5 control lines, and 8/16 data lines. Pulls 95mA typical; runs cool to the touch. (Microchip's SPI controller is really the next step WRT fewer signal lines, but IIRC it also pulls 250mA at 10Mb.)

For the jack, Bothhand NU1S041C-434 RJ-45 w/ magnetics & 3 LEDs is very popular. $3.50 each in tubes of 28 + $10 S&H from

(Some others are Delta, Pulse, Bel Fuse, HALO, MagJack, Tyco, Molex, etc.)

HTH, Richard

David Kelly schrieb:

I would also think in that direction.

Using "PC board mainstream" parts always have the risk that these probably become obsolete half a year after design-in. Chips that are targeted to industrial electronics normally have much longer lives.

--
Dipl.-Ing. Tilmann Reh
http://www.autometer.de - Elektronik nach Maß.

Why the Mega128???

Let's look at silicon costs...

Mega 128 $8.00 SRAM $1.50 Mac Phy $4.00 Ethernet Jack $1.95

Total Silicon 15.45

Freescale/Coldfire 5270 7.95 (We currently use the 150Mhz version $9.54)

512K Flash 1.25 10/100 Enet Phy 1.50 10/100 Etyhenet Jack 1.95 Total Silicon 12.65

I'd personally ad 2Mbytes of SDRAM to make things easier Total Silicon with SDRAM $14.15

over $1.00 cheaper than the MEGA 128 solution.

This gives you a far more capable unit.

100Mhz 32 bit CPU, 512K flash ,2M bytes of SRAM, 3 uarts, CAN, I2C, SPI, 16 timers, 10/100 Ethernet.

If you need A/D from the Mega then substitute a freescale 5282 for the CPU and Flash.

We offer turnkey ready to use modules based on this part You can start your software development today.

We will sell you the design, hardware, software tcp, tools,. compiler linker debugger, with full source etc..etc... . so you can produce your own modules for $24,500 This is a site license for an unlimited number of designs, with no royalties. This price includes a design review of your first hardware design based on our design. If you just wanted to produce a clone of our modules, the PCB designs are even included.

If you have realistic costing for your engineering time you would be hard pressed to do a hardware design and port a tool set, RTOS and tcpip stack to any design for 24K.

As a general comment, some people are scared by the word RTOS, it's there and it keeps all the TCP/IP services running in the background, but for your own programming you don't need to use it at all, just write your code in the way you are accustomed, a single threadof execution with interrupts providing any necessary scheduleing.

See

and

RTOS example:

Paul

It doesn't make sense with AVR, if you need ethernet.

timers,

Flash.

AT91SAM7A,7S or 7X are just as good.

AT91SAM7X seems to be your best choice. If you are concerned about 7X availabilty, goes with 7A or 7S first. If you are starting your project soon, perhaps you can get the 7X when you are ready for it. Switching from 7A or 7S to 7X is a lot easier than from AVR to ARM.

Because it's what I'm familiar with. Bad reason.

Upon further investigation, I have come to agree.

timers,

and Flash.

I am convinced. I've been looking into the availability of the AT91SAM7X, and Atmel claims the distributors will have them Oct 1. I've got calls into the distributors to see if that's for real. Only Digi-Key has responded so far, and the responses was something along the lines of "Huh? Ain't never heard of it." We'll see if anybody else comes through.

I can probably wait until mid-October to get the part. But then I have another problem -- I need a cheap Ethernet PHY (no MAC, since the

7X has on-chip MAC). And the problem is that the low-volume suppliers I usually use (Digi-Key and Mouser) have pretty poor selections of PHYs. (Digi-Key is charging ~$8+ for a simple 10/100 PHY... seems outrageous.) In fact, most of the parts I've been looking for during this project (which is a bit more complex than things I've undertaken before) are expensive or non-existant in Digi-Key's catalog, so perhaps it's time I branch out to other suppliers -- any suggestions (of suppliers and/or parts)?

Thanks,

--
Randall

How many are you trying to build? (Do you just need samples or 100.1000.10000?)

We have had good luck with the Davicom DM9161 Probably at least a 100pc minimum buy.

Micrel has some new very low cost PHY chips as well... you could probably get dsitributor samples.... (We are just starting to use some of these)

Lastly try the DP83847ALQA56A-ND $5.70 Q1 from digikey. It is a fine PHY, but be aware that placing the LLP56 package on a PCB is a bitch.

Paul

Initial prototype run of 5 units, then a first production run of about

50, and then (if all goes well), subsequent runs of 100-300. The larger runs are easy, but how do I get small quantities for prototyping?

I've seen Davicom mentioned, so I've been looking for anybody who carries Davicom, with no luck... where can I get them in the US?

Yeah, the prototypes will be hand-soldered by yours truly, so leadless packages are probably not such a good idea. How do the pros handle prototype assembly of things that can't be hand-soldered? I'm not a pro, just an amateur hack who got talked into doing this project. I guess that makes me a pro now, but I don't feel like one. In particular, trying to navigate the sea of manufacturers, parts, and distributors is getting a little overwhelming.

--
Randall

We simply order the prototype board with the part mounted. Dm9161AE (TQFP 48) is not a problem for the prototype shop. For productions, they are $2 to $4 each, depends on qty.

I just got a quote from the shop. They can provide the Dm9161AE (ethernet phy) and mount on the prototype board for $5 additional. The prototype boards are $5 to $10 each, depending on size. Mininum order of $50. See:

leadless

linnix, Randall,

Were you able to find a US distributer for direct purchase/sample of th DM9161?

Jason

This message was sent using the comp.arch.embedded web interface o

We are getting some for $3 each. How many do you need.

SAM7X samples has been seen!

--
A. P. Richelieu

There are distributors with samples right now... If you download the evaluation kit manual ,then there are some schematics with a Davcom PHY. You probably want to use RMII to save pins. If you need industrial temp range, then the Davicom part will not cut it but a micrel part cn do RMII + industrial.