Ethernet? again.

cadillackid · Post by **cadillackid** » 12 May 2010, 5:31 AM

Ok so i have been reading the forums and it seems most of the posts about ethernet are how to download firmware to the devices and the trials, tribulations associated with....

that does concern me although it seems like the ATN character method works in this regard and has been well tested...

now onto what I want to do in regards to ethernet..

yes this is for the HVAC controllers im working on.. rather than have a master controller all interconnected with multi-drop RS-485.. ive thought that ethernet would be a better way to go.. allows more flexibility as well as the fact myself and most people these days have a network in their homes.. (at least anyone who may end up with these HVAC controllers if i ever decide to go commercial)...

so my idea is right now I have a central server.. it listens on socket ports for the controllers to connect to it and then opens a line of communications between the controller and itself..

the controllers open an outbound telnet session to the server to make the establishment...

right now this is accomplished by using external Precidia ipocket-232 devices.. these devices if a connection to the host dies even drop DTR.. so i can effectively remotely reset the individual ZX-328 boards (although ive never had a need to, they just dont lock up)...

which onboard ethernet is currently going to allow me this? I have read about xports, siteplayers, and others...

however as i mentioned most of the posts are 3 or 4 years old... so what are you guys using? it looks like people originally didnt care for Xport because it is 3.3 volts.. however the docs for it say "5 volt tolerant" so my guess is you can use it at 5?

or is there a better bang for the buck?? keep in mind though cost is NOT my motivating factor.. getting it to work reliably is....
-Christopher

twesthoff · Post by **twesthoff** » 12 May 2010, 16:27 PM

I would expect one of the many serial to ethernet modules would be the
easiest. I wouldn't use the siteplayer. Check out the Wiznet modules
if you want to program with socket style interface. I have used the
Xport rs-232 modules with good results.

ZX-40 wrote:

Ok so i have been reading the forums and it seems most of the posts
about ethernet are how to download firmware to the devices and the
trials, tribulations associated with....

that does concern me although it seems like the ATN character method
works in this regard and has been well tested...

now onto what I want to do in regards to ethernet..

yes this is for the HVAC controllers im working on.. rather than have
a master controller all interconnected with multi-drop RS-485.. ive
thought that ethernet would be a better way to go.. allows more
flexibility as well as the fact myself and most people these days have
a network in their homes.. (at least anyone who may end up with these
HVAC controllers if i ever decide to go commercial)...

so my idea is right now I have a central server.. it listens on socket
ports for the controllers to connect to it and then opens a line of
communications between the controller and itself..

the controllers open an outbound telnet session to the server to make
the establishment...

right now this is accomplished by using external Precidia ipocket-232
devices.. these devices if a connection to the host dies even drop
DTR.. so i can effectively remotely reset the individual ZX-328 boards
(although ive never had a need to, they just dont lock up)...

which onboard ethernet is currently going to allow me this? I have
read about xports, siteplayers, and others...

however as i mentioned most of the posts are 3 or 4 years old... so
what are you guys using? it looks like people originally didnt care
for Xport because it is 3.3 volts.. however the docs for it say "5
volt tolerant" so my guess is you can use it at 5?

or is there a better bang for the buck?? keep in mind though cost is
NOT my motivating factor.. getting it to work reliably is....
-Christopher

stevech · Post by **stevech** » 12 May 2010, 19:42 PM

I've used Xport, WiPort (Lantronix), NPORT (Moxa)

cadillackid · Post by **cadillackid** » 14 May 2010, 14:38 PM

Ive decided to use the Xport direct.. neat little module.. getting it the 3.3 volts it needs wont be too tough.. with the enhancements made to the ZX chips in the last couple years the ATN line isnt required so I should be able to use tom port redirector and still download code into my boards..

or I may just use anothjer port on the zx for the xport.. havent decided yet.. got to get one of these bread boarded into my controller for testing then I can make the decision...

part of this depends on whether I can find CHEAP or free board layout software with an auto-router because im new at laying out boards and not looking forward to expresspcb and their manual routing layout....
-Christopher

twesthoff · Post by **twesthoff** » 14 May 2010, 20:09 PM

check out DipTrace,
http://diptrace.com/

They have a free version, and it is easy to use. Good support too.

ZX-40 wrote:

Ive decided to use the Xport direct.. neat little module.. getting it the 3.3 volts it needs wont be too tough.. with the enhancements made to the ZX chips in the last couple years the ATN line isnt required so I should be able to use tom port redirector and still download code into my boards..

or I may just use anothjer port on the zx for the xport.. havent decided yet.. got to get one of these bread boarded into my controller for testing then I can make the decision...

part of this depends on whether I can find CHEAP or free board layout software with an auto-router because im new at laying out boards and not looking forward to expresspcb and their manual routing layout....
-Christopher

stevech · Post by **stevech** » 14 May 2010, 20:29 PM

Don and others here are PCB veterans. Me, not so much.

I just did a small (business card sized) board with ExpressPCB. Quite easy to manually route. Even with auto-route, and without spending $$$$ for such software, I suspect a lot of time is spent manually routing anyway. I don't do enough PCBs to justify the learning curve or expense of the full-up tools.

I tried for hours to use three auto-routing tools, one being DipTrace, but the learning curve was just too steep for what I wanted to do. (Some time back I tried and discarded Eagle -free but has a horrible user interface).

With ExpressPCB, be sure to draw a schematic and keep it linked to the PCB design. Speeds things up, helps avoid mistakes.

Enclosed is screen grab of PCB design with the ground plane copper pours turned off. The actual boards have copper pours on both sides. It's a small daughtercard with a WizNet 812MJ ethernet/TCP board (SPI) and a Digi XBee, and I/O connectors. It plugs into the pin header of a purchased microprocessor board. The holes running vertically on the left edge mate with the standard pin header. Each hole has within it a MIL-MAX gold insert that has tiny internal springs and mates with the pin header.

It's not a trivial board, but it was easy to do. I ran the first ones with solder mask and silk screen lettering. There was one small error- corrected with a quick 1/8 in jumper. Works as intended!

It's fun to see your artwork in real form!

cadillackid · Post by **cadillackid** » 15 May 2010, 4:08 AM

that board looks good.. I think i'll give a shot with manual routing.. my board just has a zx-328 (trying to get a zx-328nu but cannot get any response from anyone at oak micros.. are they still in business?)

i'll have the xport direct, a ds-1267, a few pullup resistors and some caps N such and some connectors.. but really I guess pretty simple...

hence one of the reasons im choosing the 328nu because it has alot of the support circuitry on board.. I also have tried eagle and iot was terrible..

my father talked about getting me on his Or-cad and some other layoput program but i have yet to do that...
-Christopher