I have read and combed through so many pages on this website for some months now, searching for home automation ideas. All I see and heard is RS-232. Okay, now my question is: for example, I have 3 lutron grafik eye, 1 universal remote MSC 400, yamaha music server. All this equipment are capable of using Rs-232. How does one interlink all this devices together with RS232 to a pc so that I can use MainLobby to control it. Do I need a multiple rs232 port cable to connect all rs232 device to my pc. I'm confused about all this rs-232. Please I need someone to explain to me. I will really appreciate it. Also, in the event that one needs to interlink some devices such as music server, video server, lighting, HVAC, thermostat thru RS232. Do they all connect to a box that has multiple rs232 port. In other words, one end of a RS232 cable goes into each equipment, then the other end all meet at a multiple port box? HELP!!!
Home Automation RS 232
- Thread starter gasbie
- Start date
Most people have an add-on module (or USB nowadays) which adds more serial ports to their PC. I personally have a network based unit, which gives me 4 extra serial ports per expander, and allows me to place it in a remote location since all I need is network access.
mustangcoupe
Senior Member
Basically YES, a computer with multiple RS-232 ports is needed
BUT One thing you can do is get a USB -> RS-232 (multiple port) or Ethernet -> RS232 boxes. Lantronics makes one, Digi makes one, and quatech is another brand which was found on ebay really cheep last year ($25 bucks for a 4 port model) add in some drivers and you have a virtual hardware RS-232 port that will look like a regular RS232 port to your software
BUT One thing you can do is get a USB -> RS-232 (multiple port) or Ethernet -> RS232 boxes. Lantronics makes one, Digi makes one, and quatech is another brand which was found on ebay really cheep last year ($25 bucks for a 4 port model) add in some drivers and you have a virtual hardware RS-232 port that will look like a regular RS232 port to your software
Deane Johnson
Active Member
I just went through this, wanting the cheapest way to get more serial (RS-232) ports on my computer. I bought a powered USB hub and some of the cheap Amazon USB to Serial converter cords and all works well.
I'm running the VRC0P, an ACTTi103, a USB-UIRT, among other things with no glitches.
Deane
I'm running the VRC0P, an ACTTi103, a USB-UIRT, among other things with no glitches.
Deane
znelbok
Active Member
Yes, RS232 is a poin to point wiring system, so you will need a single serial port for every device you want to connect.
As indicated , pleople are using ethernet to RS232 and USB to RS232. This creates "virtual" serial ports on the host computer and to the software using the serial port, it does not know any different.
Notice here that I have intercahnged the words RS232 and serial. RS232 is a serial connection, but so is RS422 and RS485. These are same but different and dont get too concerneed about them.
How you pyhsically connect the cable is up to you, but a well tested methid is to use cat5 for the long runs and a cat5 to DE9 adapter at each end (if required). DE9 is the stnadard D shaped 9 pin connector ont he back of a PC that is typically used for serial connections. You can also get a serial port with a DB25 connector as well.
Once you have your physical cable and plugs sorted out, you then need to understand what type of device you have, is it a DCT or DCE, basically, do you need a cross over connection or not. Most of the time its a cross over connection.
Most devices make it easy and only use three wires, Recieve, transmit and ground. Rx goes to Tx, Tx goes to Rx and Gnd to Gnd. SOme devices will want extra wires connected for handshaking etc, this is usually indicated in the manual for the device.
Search for RS232 pinouts on google and you will get lots of diagrams on how to connect devices together.
Hope this helps and does not confuse you too much
Mick
Thanks guys for all your quick response. I really appreciate it. I'm learning a lot from everyone. Thanks again. So I have a good idea of was RS232 is now. I still have series of questions that got me confused.
1) Is rs232 the same as DB9?
2) I saw this at monoprice: http://www.monoprice.com/products/product....=1&format=2
Will this work for connecting my equipments to the computer?
3) If I want to use a cat 5e for the Rs232 connection, that mean I need a M/F connector at the end of the cable, am I correct.
4) Where can I get a good ethernet to rs232 mulitport box? Am also guessing that this box will have multiple rs232 port and one ethernet port. And the box will connect to my pc through the ethernet port. Am I correct?
5)My equipment room will be on the middle floor and my ethernet wires from every nook and corner of my house drops in my basement. So Am guessing that I need to run sever cat5e cable (for rs232 connection) from my equipment closet to the basement?
6) What kind of thermostat can I use in my house that has the capability of rs232 or that I can control over the ethernet cable?
7) Will I need some to help connect my HVAC to my home automation or its a DIY project?
I'm sorry that I have some many questions. I just want to do this right since my ceiling and parts of my walls are down right now for renovation. So any pictures will help. Thanks of all contribution.
1) Is rs232 the same as DB9?
2) I saw this at monoprice: http://www.monoprice.com/products/product....=1&format=2
Will this work for connecting my equipments to the computer?
3) If I want to use a cat 5e for the Rs232 connection, that mean I need a M/F connector at the end of the cable, am I correct.
4) Where can I get a good ethernet to rs232 mulitport box? Am also guessing that this box will have multiple rs232 port and one ethernet port. And the box will connect to my pc through the ethernet port. Am I correct?
5)My equipment room will be on the middle floor and my ethernet wires from every nook and corner of my house drops in my basement. So Am guessing that I need to run sever cat5e cable (for rs232 connection) from my equipment closet to the basement?
6) What kind of thermostat can I use in my house that has the capability of rs232 or that I can control over the ethernet cable?
7) Will I need some to help connect my HVAC to my home automation or its a DIY project?
I'm sorry that I have some many questions. I just want to do this right since my ceiling and parts of my walls are down right now for renovation. So any pictures will help. Thanks of all contribution.
myambience
New Member
I may be a bit late, but here are some answers....
RS232 is a communications protocol. A DB9 is a type of connector. The DB9 connector is commonly used in RS232 or Serial communication, but not always.
A general swipe at the rest....
Generally, thermostats do not use RS232 for communication, they use 485. Here is some background. RS232 has a reliability issue when the run gets longer than 50'. RS485, on the other hand can run up to 4,000'. RS485 can also be "daisy chained" (this means you can run from stat1 to stat2 to stat3). Everything does not have to be "home run" wired. RS485 is fast and ultra reliable.
So, we see two main thermostat players: RCS and AprilAire. Both of these are based on RS485 and use a RS232 to RS485 hub. (This is not absolutely required).
Differences?? The RCS unit will require a CAT5 to be run from your processor (computer) to the HVAC unit. AprilAire will require CAT5 to get to the thermostat. The latter is often difficult in retrofit.
Back to the hub.... You can get a USB to RS485 dongle for your processor and run CAT5 from it to the HVAC units (RCS)
OK....maybe this is getting a bit deep. I will stop here for now.
Hope this helps! If you have more questions, I would be happy.
DH
RS232 is a communications protocol. A DB9 is a type of connector. The DB9 connector is commonly used in RS232 or Serial communication, but not always.
A general swipe at the rest....
Generally, thermostats do not use RS232 for communication, they use 485. Here is some background. RS232 has a reliability issue when the run gets longer than 50'. RS485, on the other hand can run up to 4,000'. RS485 can also be "daisy chained" (this means you can run from stat1 to stat2 to stat3). Everything does not have to be "home run" wired. RS485 is fast and ultra reliable.
So, we see two main thermostat players: RCS and AprilAire. Both of these are based on RS485 and use a RS232 to RS485 hub. (This is not absolutely required).
Differences?? The RCS unit will require a CAT5 to be run from your processor (computer) to the HVAC unit. AprilAire will require CAT5 to get to the thermostat. The latter is often difficult in retrofit.
Back to the hub.... You can get a USB to RS485 dongle for your processor and run CAT5 from it to the HVAC units (RCS)
OK....maybe this is getting a bit deep. I will stop here for now.
Hope this helps! If you have more questions, I would be happy.
DH
Steve
Senior Member
Don't leave out the HAI RC1000/2000. They compare very favorable to the RCS and Aprilaire stats. There are also Zigbee based, UPB based and other specialty thermostats available.
myambience
New Member
You are absolutely correct. Just trying to shed some RS232 light!
There are many options.
There are many options.
pete_c
Guru
Over the years (5-6) of using multiple RS-232 devices I've made small RJ-45 to RS-232 converters and moved anything over 10' to Cat5.
Today utilizing these longer RS-232 runs for my Sprinkler system (Rain8's, W800's and RFID Recievers). Historically in my old home utilized same setup to bring the CM11 X10 controller adjacent to the fuse panel where as the server was probably some 30 feet away.
I currently have 18 plus serial RS-232 devices plugged into my HS server. Its current setup is 2 Digi USB to 8 port boxes going to one Digi 7 port USB hub. In addition I also utilize a Digi USB anywhere box and a couple of Quantech RS-232 to IP boxes. They all work fine with everything except my USB sound devices and USB Way2Call device. I have two RS-232 ports on my HA server today (COM1 & COM2) which I utilize to test new devices.
Works for me and its easy now with different MFGs USB to serial devices.
You can buy higher end USB to Serial boxes refurbished or Serial to Ethernet on Ebay for a fraction of the original cost. (that I how I purchased my Digi boxes and Quantech boxes). The older serial/parallel boxes (larger) can be had very reasonably. Now you can even purchased decent high end Wireless (802.XX) serial boxes which work fine.
Today utilizing these longer RS-232 runs for my Sprinkler system (Rain8's, W800's and RFID Recievers). Historically in my old home utilized same setup to bring the CM11 X10 controller adjacent to the fuse panel where as the server was probably some 30 feet away.
I currently have 18 plus serial RS-232 devices plugged into my HS server. Its current setup is 2 Digi USB to 8 port boxes going to one Digi 7 port USB hub. In addition I also utilize a Digi USB anywhere box and a couple of Quantech RS-232 to IP boxes. They all work fine with everything except my USB sound devices and USB Way2Call device. I have two RS-232 ports on my HA server today (COM1 & COM2) which I utilize to test new devices.
Works for me and its easy now with different MFGs USB to serial devices.
You can buy higher end USB to Serial boxes refurbished or Serial to Ethernet on Ebay for a fraction of the original cost. (that I how I purchased my Digi boxes and Quantech boxes). The older serial/parallel boxes (larger) can be had very reasonably. Now you can even purchased decent high end Wireless (802.XX) serial boxes which work fine.
