Lots of I/O

jbauer

Member
Hey guys,

What are some of the normally accepted ways to get lots of I/O into your HA server? I'm looking for both contact closures and analog inputs. Lets say 50 contact closures and 10 analog inputs, but I'm flexible (and I suppose 48 and 8 would be much more "powers of 2'ish").

I prefer a USB interface.

All suggestions are appreciated, please innudate me with ideas. I've done a lot of research on this topic, and have still not seen what I'm looking for.

- jason
 
I use Homeseer and Applied Digital I/O (Leopard, (2)Secu16Is & a Secu16 gets me 40 inputs), it is serial interface however, and you'd need (4) Secu16 modules plus an Ocelot to get 64 inputs.

On the plus side, it can run mission critical stuff w/o a computer, and be expanded to handle IR, voice announcements, X10 etc.


Applied Digital Web Site Applied Digital Web Site


Pete C
 
jason;

May I ask a few questions of you first? This will help the selection process.

What are you doing with your contact closure inputs? Are they part of a security system? What HA software do you plan on using?

Concerning your analog inputs, what voltage levels do you need? What accuracy (bit resolution) is needed? Do you need to read both positive and negative voltages? Again, what HA interface will you use to read these values? Do they need to have a logic tie with your contact closure inputs? Will you need to act on various limits?
 
You could use an ELK M1 or EZ8 with USB to RS232 converter or M1XEP Ethernet Module and get up to 208 inputs and 205 outputs with input output expanders. It would give you the power supply built in. Many of the home automation software packages like CQC and Homeseer interface to it. There is an open ASCII protocol to roll your own software.
 
Spanky said:
You could use an ELK M1 or EZ8 with USB to RS232 converter or M1XEP Ethernet Module and get up to 208 inputs and 205 outputs with input output expanders. It would give you the power supply built in. Many of the home automation software packages like CQC and Homeseer interface to it. There is an open ASCII protocol to roll your own software.
Very true. The analog inputs might be a challenging request for the Elk though depending on the sensors/applications needed/used. <_<
 
BraveSirRobbin said:
What are you doing with your contact closure inputs? Are they part of a security system? What HA software do you plan on using?

Concerning your analog inputs, what voltage levels do you need? What accuracy (bit resolution) is needed?

Do you need to read both positive and negative voltages?

Again, what HA interface will you use to read these values?

Do they need to have a logic tie with your contact closure inputs?

Will you need to act on various limits?
The contact closure inputs will trigger HA events and be part of security. As far as the software is concerned, I like PowerHome because it seems to be the most flexible, and with the scripting engine I can add support for any module you can throw at me. I am an experienced programmer.

The analog inputs... 0 to +5 vollts would be fine, 8 to 12 bits would work. Obviously 12 bits would be great, but I'd settle for 8. I can use op amps to scale the voltage source to whatever range the ADC needs, so that is not really a concern either.

Negative is not necessary, again op amps are my friends.

The analog and digital will be used together, yes. I do need limits on the analog, such as "If input24 goes high and analog3 > 3.5 then".

Thanks for all of the replies so far. I'm really looking for the most # of inputs for the least cost. Software support is not a problem, I will write any wrapper code that is needed to glue the project together.

- jason
 
BraveSirRobbin said:
Very true. The analog inputs might be a challenging request for the Elk though depending on the sensors/applications needed/used. <_<
Please elaborate on this. I have heard that the Elk can be very limiting like this, but I have never heard exactly why. I have thought about an Elk on many occasions, but I'm sure that the stuff I do is just a little too advanced for it.

Can you give an example of something that the Elk CAN NOT do?

- jason
 
dwayne said:
Ontrak Control Systems

This company has a wide selection of RS232 and USB analog/digital i/o boards. Programming is simple serial commands. I have used them on several HA projects successfully.
These look promising. This is the sort of stuff that I was hoping to get posted back. Any other suggestions out there?

- jason
 
There is the Velleman k8001, which PH supports...

The card itself has 16 optically isolated digital connections, which can be freely chosen as either inputs or outputs (eg. 6 inputs and 10 outputs) according to how they are set up by the user. Furthermore, the card has 9 analogue outputs, of which one is high precision, and 4 analogue inputs. If this capacity is not sufficient for a particular application then up to 4 cards can be connected together (1 master and 3 slaves), such that an enormous potential exists.

http://www.vellemanusa.com/us/enu/product/...t.asp?id=350602
 
Not sure you can say 64 Opto inputs represents "enormous potential"... I use 80 today and I still need room to expand. I always felt the Velleman stuff was not scalable enough which is why I am so anxious for PH to start supporting the M1.
 
I'm a big fan of SeaLevel Systems. While I haven't used them for HA applications before (yet), I have used them many times in an industrial setting with no problems. They have analog and digital I/O devices that communicate over your choice of RS232/485, USB, or Ethernet. You can download the drivers and check out their protocol and programming docs on their site.

Terry

Edit: Specifically for your needs: check out the USB-> I/O modules here. The 48 and 96 port TTL digital devices are $229 and $279 respectively. The analog devices are more pricey, but they have several to choose from. Also, remember that you can use the "old-school" game adapter on a PC and get 4 8-bit analog ports.
 
FYI:
The ELK M1 serial RS-232 Data Protocol feeds back the analog voltage of the individual zones with 1/10 Volt resolution. What you are doing with the analog voltage determines if this resolution is good enough.

Here is the section out of the RS-232 Protocol Document explaining how to request and the zone analog reply from the M1 family:

4.27 Zone Analog Voltage
This command allows automation equipment to request a zone analog voltage level. M1 Version 4.2.8 and after.
Request Zone Voltage (zv)
09 – Length as hex
zv – Get command for zone analog voltage data
ZZZ – Zone number 001 to 208 as 3 ASCII characters decimal
00 – future use
CC – Checksum
Example: 09zv12300B1 Zone 123 analog voltage request data


Reply Zone Analog Voltage Data (ZV)
0C – Length as hex
ZV – Reply with zone definition data
ZZZ – Zone number 001 to 208 as 3 ASCII characters decimal
DDD – Zone voltage data as 3 decimal ASCII characters. Divide data value by 10. Right character is the tenths decimal place.
00 – future use
CC – Checksum
Example: 0CZV123072004E Zone 123 , voltage is 7.2 volts
 
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