my profile | my password | search | faq & rules | forum home

» Film-Tech Forum ARCHIVE   » Operations   » Digital Cinema Forum   » Serial to Ethernet bridge for automation (Page 2)

This topic comprises 2 pages: 1  2

Author Topic: Serial to Ethernet bridge for automation Steve Guttag We forgot the crackers Gromit!!! Posts: 12814 From: Annapolis, MD Registered: Dec 1999 posted 05-28-2013 04:08 PM                     RS232 is certainly a more robust medium than Ethernet. However, it is dependent on the people creating the RS232 protocol for each device and some are pretty bad at it. I guess the same can be true for Ethernet. RS232 is generally a 1:1 situation...which can be good and bad...nothing to much up the communication and timing is normally perfect. More difficult for remote "monitoring." Ethernet wins when it comes to remote monitoring with multiple devices talking to the same piece. Long term though...things are moving more and more Ethernet and away from RS232.  |  IP: Logged Stephen Furley Film God Posts: 3059 From: Coulsdon, Croydon, England Registered: May 2002 posted 05-29-2013 07:53 AM                     Ethernet to controller then some sort of serial to the devices being controlled is very common. The serial isn't always RS-232; RS-422 is often used for greater distances, and RS-485 for multiple devices on a serial bus. This is how our entrance barriers are controlled, and our lighting in the new and refurbished parts of the building, and the few CCTV cameras which have pan, tilt and zoom. All of these systems are managed by outside companies; we provide them with an Ethernet connection wherever they want to put their controllers, and usually with a VPN connection which allows connection only to the system which their company manages. Most problems are dealt with by one of their engineers coming in over the Internet from whereever they happen to be on their laptop. We certainly have hundreds, possibly over a thousand, devices controlled in this way. The lighting is DALI lighting will come up as someone enters an area, and go down again a few minutes after they leave. The DALI controllers talk to each other via Ethernet and the whole lot talks to a control and monitoring station in the office of one of our premesis staff, and via the VPN to the lighting company. Works well in our situation, but seems like overkill if all you want to control is one device, in the same room.  |  IP: Logged Stephen Furley Film God Posts: 3059 From: Coulsdon, Croydon, England Registered: May 2002 posted 05-29-2013 09:44 AM                     Here are some pictures of some of this equipment, Ethernet to single port and multi-port serial, and Ethernet to serial to DALI. These are the barriers: There are five lanes, two out of sight to the left. In the distance are another, similar set. Each of the ten has two contactless smart card readers, one inside and one outside. This is what controls them: The white box at the top left has four Ethernet ports in it, two in use. One red cable feeds the small grey box just below it, which is a single port serial gateway device with an external power supply; I'm not sure what it is used for. This is the sort of thing that James was asking about. The other red Ethernet cable is connected to the top left large card. These cards are all connected together in a daisy-chain, via RS-485 I think, and then the cards connect to the barriers via twisted pairs, presumably RS-422. This thing is huge, the cards are almost as big as a sheet of Letter size paper. I've no idea why they're so big. The two large white boxes are power supplies and the thick red cables on the left side are connected into the fire alarm loops, so that all of the barriers open if the fire alarm is activated. A single card of the type with an Ethernet connection is also installed in white boxes around the building to control access to various doors. Most are hidden above ceilings, but this one is visible, in our PABX room: Finally, a lighting controller box, there are about a dozen of these located in various service risers around the building: This time the Ethernet cable is grey, and comes into the black box near the centre, with 'Control' on it. The eight green cables coming out of the bottom of this are eight serial ports, which go just a short distance, to the devices with the green lights, mounted on the bottom of the box door; these are the DALI controllers. The white things above them are their power supplies, with brown and blue mains wires looped into each. Each DALI controller can talk to up to 64 devices, lamp ballasts, sensors etc. The DALI bus uses just two wires for data, rather than a wire, or pair of wires, to each device, as with 0-10 V or 1-10 V analogue lighting control systems.  |  IP: Logged James Skinner Film Handler Posts: 22 From: Wolfville, Nova Scotia, Canada Registered: Dec 2012 posted 06-02-2013 06:46 PM                     I have been trying to get the Doremi serial automation working and so far haven't had much luck. I have an external box that I am trying to control that uses 5 bytes for each control signal. I've connected this box to a regular PC via serial and was able to successfully send command to it so I know that it works. I then connected it up to the Doremi 2K4 serial port. I created a new device in the Device Manager for it with the proper transmission parameters. Next I tried to create a Macro to send some commands to it. The first problem that I encountered was that the Doremi macro editor only seems to be able to specify data in ASCII or binary. The control command that I have are specified in hex. Is there way to input hex characters in the marco editor using the Raw Send Message feature? I might have been able to figure it out better if I could see responses from the serial port on the Doremi. I couldn't even tell if it was receiving anything I sent it. When running a macro I could find no way to see the response from the external device? Does anyone know if its possible to specify the bytes sent in a Raw Send Message on a Doremi in hex? Also is there anyway to monitor the data being sent back from a connected serial device for debugging purposes?  |  IP: Logged System Notices Forum Watchdog / Soup Nazi Posts: 215 Registered: Apr 2004 posted 06-05-2019 02:48 AM                 It has been 2193 days since the last post.  |  IP: Logged Spencer Krit Film Handler Posts: 1 From: Madrid / Spain Registered: Jun 2019 posted 06-05-2019 02:48 AM                     How did you try to monitor the data that Doremi transmits? Try using the serial port monitor to view information. This software accepts ASCII data format. The program is free, so feel free to try  |  IP: Logged Gordon McLeod Film God Posts: 9532 From: Toronto Ontario Canada Registered: Jun 99 posted 06-05-2019 10:17 AM                     The usual issue with DOREMI and RS232 is that it works best if you write your commands in hex Also it requires the line feed carriage return typed in We use Termite to view rs232 or serial talk which is in the warehouse here i believe  |  IP: Logged Leo Enticknap Film God Posts: 7474 From: Loma Linda, CA Registered: Jul 2000 posted 06-05-2019 09:33 PM                        The Xeta Converter is a good workaround. They're a little fiddly to set up (this is split between a web UI and an app), but once configured, they work pretty well. Of course it's another machine in the system, and thus another potential failure point, but if upgrading the device that needs to send and/or receive the RS232 commands to one that can handle IP is not an option, it's a viable alternative.  |  IP: Logged

All times are Central (GMT -6:00)

This topic comprises 2 pages: 1  2

Printer-friendly view of this topic

Hop To: Select a Forum: Category: Operations -------------------- Digital Cinema Forum Film Handlers' Forum Large Format Forum Ground Level Feature Info, Trailer Attachments & REAL Credit Offsets Category: Community -------------------- Film-Yak Film Handlers' Movie Reviews The Afterlife Bob Maar's Joke-A-Thon Category: Classified -------------------- Equipment and Supplies Wanted/For Sale Help Wanted/Seeking Employment Category: System -------------------- Software Beta Testing Forum

The Film-Tech Forums are designed for various members related to the cinema industry to express their opinions, viewpoints and testimonials on various products, services and events based upon speculation, personal knowledge and factual information through use, therefore all views represented here allow no liability upon the publishers of this web site and the owners of said views assume no liability for any ill will resulting from these postings. The posts made here are for educational as well as entertainment purposes and as such anyone viewing this portion of the website must accept these views as statements of the author of that opinion and agrees to release the authors from any and all liability.