ddl@husc6.HARVARD.EDU (Dan Lanciani) (08/17/86)
There has occasionally been interest in BSR/computer interfaces expressed on the net. While setting up my system, I have purchased and worked with what are probably the three most popular versions. (In any event, they are the only ones I found...) I have no interest in any of the companies and this information is based on personal experience only. The three units are, in no particular order: the Heath GD-1530 purchased as a kit at retail ~$100, the X-10 Powerhouse Computer Interface purchased from DAK mail order ~$50, and the Radio Shack Color Computer Plug'n Power interface purchased on sale ~$40. The Heath GD-1530 requires a grounded outlet and receives RS-232 input at up to 2400 baud from the computer via an opto-isolator. The grounded case and opto-isolator provide protection from the internal circuit which floats at one side of the line. No provision is made for returning data to the computer; in fact, there are only two pins in the RS-232 connector. A simple command set allows generation of any standard BSR command; commands consist of a house code followed by a number or function: [A-P][ON|OFF|A|C|BR|DIM|[1-16]] (A=all lights on, C=all off). Unfortunately, the GD-1530 would not function correctly in my home. Many lights which work correctly from a standard BSR controller or timer will not respond to commands from the GD-1530. Modules connected near to the GD-1530 work fine, so this may not be a problem for some. (The unit has been sent to Heath for examination and they declare it to function normally; I have observed that the output signal is somewhat distorted but this may be unrelated.) The X-10 Powerhouse Computer Interface operates at 600 baud only and does not require a grounded outlet. It would appear that it is optically isolated at the output transformer. Communication uses a "packet" oriented format rather than ASCII commands with each packet acknowledged by the controller. In addition to the expected direct commands, this unit includes a 128-event timer and a real-time clock which can switch modules on and off without computer attention. The clock, timer, and a small area of general-purpose memory are protected against power failure by a 9-volt battery. The general-purpose memory is used by the supplied software to "remember" module locations. Since I do not have a computer supported by X-10 (most popular brands are available) I used the detailed protocol description supplied to write my own software. Those desiring a standard RS-232 interface should order the version for the IBM-PC as it includes the correct cable. Finally, the X-10 unit includes 8 switches for direct control of units 1-8 of the "base" housecode (a settable option). The Radio Shack controller is very similar to the X-10; however, it has only 4 on/off switches for direct control and is somewhat smaller. Programming information is not supplied but the included program pack does most of what one might want for simple applications. Connection is through the Color Computer's Cassette port, freeing the RS-232 port for other uses. Of course, if you don't have a Color Computer this won't do you much good... I will be happy to mail further information (if I have it) to anyone interested. * [a-zA-Z]* is a trademark of [a-zA-Z]* * The information herein does not necessarily apply in *this* universe. Dan Lanciani ddl@harvard.*
bob@multivu.UUCP (Bob Hutson) (08/18/86)
In article <184@husc6.HARVARD.EDU> ddl@husc6.HARVARD.EDU (Dan Lanciani) writes: > > There has occasionally been interest in BSR/computer interfaces >expressed on the net. > ..... >Unfortunately, the GD-1530 would not function correctly in my home. Many >lights which work correctly from a standard BSR controller or timer will >not respond to commands from the GD-1530. I have the same problem. In my case, the problem was traced to the fuse. It's a 1/8 amp fuse with a 22 ohm resister mounted inside the glass (in series with the fuse element). It appears as though a significant portion of the signal is being dropped across this resister. A BSR unit contains an almost identical output curcuit but without the resister. As a test, I tried replacing the fuse with a normal fast-blow of the same rating. This solved the problem but cannot be considered as a final solution. I don't understand the function of the resister, but I'm sure Heathkit had something in mind when they designed it in. If anyone could enlighten me as to its purpose in life, a proper solution should be almost trivial. Please reply via e-mail. I'll contact Heathkit before summarizing. Thanks in advance. -- ~ bob ========================================================================= Bob Hutson (408) 946-6700 x4131 ucbvax!ucdavis \ -- !lll-crg!lll-lcc!vecpyr!altos86!multivu!bob seismo /
munck@mitre-bedford.arpa (Bob Munck) (08/18/86)
A small addendum to Dan Lanciani's excellent posting on the various
BSR X-10 computer interfaces. For many years, I've been using the OLD
Radio Shack Plug'n Power for the Color Computer. This is a small grey
box that also uses the cassette port; the cassette recorder can then be
plugged into it and one or the other selected by a switch on the Plug'n
Power (I imagine the new version has the same capability).
The old P'nP has a much lower level interface: it is essentially a
200KHz oscillator connected to the power lines and triggered by an
output signal from the cassette port and a zero-crossing detector that
pulses the cassette input when the power line current crosses zero (i.e.
once every 1/120 second). BSR signals are synchronized to this
zero-crossing time. It is up to software in the CoCo to wait for the
input pulse and then generate the right coding and timing of output
pulses. I had to reverse-engineer the RS-supplied software, with help
from Steve Ciarcia's article in Popular Electronics (RIP), to be able to
write my own support. Two weeks after I succeeded, RAINBOW published a
program that did the same thing.
WISH: I'm happy with the old P'nP I have, except that I really would
like INPUT as well as output. That is, I'd like a 200Khz detector that
would pulse an input line; I could then write software to decode the
received signal. Given this, I could use regular command consoles (and
the telephone interface, burglar alarm interface, etc) to send commands
to the CoCo on one set of house codes and have it control devices on
another set. It would therefore know the current state of all devices
and be able to "refresh" the state at intervals. Also, my CoCo can
(Real Soon Now) drive IR emitters with the right signals to imitate all
the remote controllers of my stereo, VCR, LaserDisk, ceiling fan, and
artificial cat; with proper coding, I could use X-10 consoles to control
all of them as well.
-- Bob Munck, MITRE
ARPA: munck@mitre-bedford
uucp: {allegra,genrad,ihnp4,utzoo,philabs,decvax}!linus!mbunix!munck
work: The MITRE Corporation, MS A430, Bedford, MA 01730
(617)271-3671 room 3A230
home: 9 Kendall Road, Lexington, MA 02173-7118
(617)861-8846tomh@hpfcms.HP.COM ( Tom Huigbretse ) (08/26/86)
I just called DAK. They dropped the price on the controller (IBM version) to $20.00!