Note: Descriptions are shown in the official language in which they were submitted.
J
BACKGROUND Ox THE INVENTION.
This invention relates to electrical appliance
control and particularly concerns a transmitter or
controller for the remote control of slave units.
US Patent No. 1592971 discloses a remote
control system for electrical appliances. That
system comprises a power main having a plurality
of pyre outlets, at least one slave unit having
a power input coupled to the main and operable to
control the supply of power to an appliance, and
a transmitter for controlling the or each slave
unit, the transmitter comprising: means for generating
selectively digital instruction signals at least some
of which contain an address of a slave unit; and means
I for modulating said digital signal onto the power main,
and the or each slave unit comprising- means for de-
fining the address of that unit; means for receiving
the digital signal from the main and means for rev
sponging to that signal when the address of the de-
fining means and any address contained in the digital signal have a predetermined correspondence,
Such a system will hereinafter be referred
to as a "system as herein defined",
Preferably the address in such a system
includes an area code or address defining an area
I
2.
building or home in which the system is to operate.
In one practical form, the system has various types of -transmitters
such as command consoles timers and computer interfaces all of which
are designed to transmit a digitally encoded 12QKHz signal onto a dour
eschew or other power line. This signal is received by various types of
slave units (receivers) such as lamp dimmers, Hall switch divers and
appliance modules which can then turn on or off appliances an dim or
brighten lamps upon receipt of the appropriate code from a transmitter.
All types of transmitters send the same code format so that
a receiver will respond to codes from any type of transmitter
in the system. A control system for a vehicle is disclosed in US
specification No. 1607816 (Belgian Specification No. 874722) and
Rich uses digital control signals containing addresses. over,
the power supply and signal path are distinct, although in one cable,
so this system is not applicable directly to a domestic control
system as disclosed in US Specification No. 1592971. Each trays-
miller is preset to communicate only with selected local processing
wits.
An object of the present invention is to provide a transmitter
(or controller high can be designed for controlling thy same types
of receiver as do the transmitters described in the above mentioned
Patent and which has improved facilities
I I
SIJMMARY OF THE INVENTION
An aspic of the invention is as follows:
A transmitter for controlling slave units by
means of a digital control signal transmitted onto a
5 power main, the transmitter comprising:
means for inputting an instruction to define said
digital control signals;
means for storing said instruction;
means for generating, and transmitting onto said
10 power main, said digital control signal corresponding to
the stored instruction;
timing means for delaying the transmission of said
digital control signal until the timing means has
completed the timing of a given time;
means for monitoring the power main for detecting
digital signals and noise of a given property; and
means for causing the timing means to recommence
its timing when the monitoring means detects signals of
said given property, whereby the transmission of said
20 digital control signal is delayed until the main has been
free of signals of said given property for said given
time.
I OOZE
4.
For example, the given time may be eight half cycles. The
given property is preferably frequency range and may be detected as
the existence of more than a given number o-f cycles within a given
time slot or slots in a half-cycle of the mains. The given slot
or slots is or are to be chosen to coincide with possible transmit-
soon time, e.g. a one millisecond slot three times each half-cycle
corresponding approximately to the zero-crossings of each phase of
a 3-phase system.
The design of the circuit is therefore prefer-
ably such that no two transmitters will try to engage
the main together. In the above example, each trays-
miller continually monitors the line for signals or
noise) and will not transmit until the main has been
free for eight mains half cycles. Also, in the pro-
furred embodiment, all transmitters waiting to engage the line will not try to do so -together. All trays-
millers in such a system are synchronized by any data
on the line and the "Priority" of each transmitter is
set by -the above-mentioned address selector switch
such that no transmitter will engage the line until
it is its "turn". The effect is intended that trays-
millers on the same phase will not interfere provided
the selector switch settings are different, and even
if two transmitters have the same setting, they will
not interfere if they are on different phases. How-
ever, once a transmitter has engaged the mains it by-
passes the polling system and can continue to trays-
mix signals without having to reengage the main each
time, (unless data is keyed in at a rate slower than
the transmission rate).
I
GRIEF DESCRIPTION OF THE DRAWINGS.
For a better understanding of the invention,
and to show how the same may be carried into effect,
reference will now be made, by way of example, to the
accompanying drawings, in which:
Figure 1 is a perspective and partially cut-
away view of a plug-in keyboard for an appliance
control transmitter;
Figure 2 is a perspective view of the main
body of the transmitter;
Figure 3 is a circuit diagram of a first
circuit within the main body;
Figure 4 is a circuit diagram of a second air-
cult within the main body; and
Figure 5 Audi spa show a block diagram of an integrated
circuit within the main body.
I
DESCRIPTION OF A PREFERRED E.~lBODI~lE~T.
One practical form of the transmitter or con-
troller discussed in said US Patent 1,592,971 is
designed to control up to sixteen receiver modules
(slave units) by pressing any of the sixteen numb
bier (or Dress keys, to create a nurser (address) code, follotved
by a junction key, (e.g. On, Off, Bright to create a function.
The transmitter described hereinbelow and chutney in Figures 1 and 2
has four rocker type switches 1 and its circuitry
is designed such that pressing one side of a rocker
twill send a number (address) code, automatically followed by the
'ON' code, and pressing the other side of the rocker will send a
no or (address) code, automatically followed by the 'OFF' code.
Receiver modules can thus be turned 'ON' or 'OFF'
with a single key operation, which is a convenience
to the user. As shown in the drawings, the trays-
miller is designed for use on 120V domestic mains
in the United States of America, but can easily be
adapted for other circumstances.
The transmitter is extremely compact, being
designed to fit into a standard wall outlet, no-
placing an existing wall switch. For this reason,
it only has four address ON~OFF"rocker switches. It
is still possible to control up to sixteen receiver
modules, however, as it has a 16-position selector
switch 2 (Figure 2) which allows the user to set
which group of receiver modules is to be controlled,
i.e. it the selector switch is set in one position,
the four rocker switches can turn on and off mod-
vies having addresses 1, 2, 3 and 4. If it is set to
the next position, the rocker switches will control
modules 2, 3, 4 and 5 If set to the fourteenth
position, modules 14, 15, 16 and 1 can be controlled,
and so on, Thus, any sequence of four successive
module addresses can be controlled, the selector
switch 2 setting the start address of the sequence.
The switches 1 are carried by a keyboard section 3
(Figure 1) which is plugged into a main body (Fig-
use 2), several versions of keyboard section being
available so as to give options such as Bright-Dim
rocker switch, or an All Lights On All Off rocker
switch,
Looking at the keyboard section in more
detail it includes a simple printed circuit board
from which project eight pins 6. The outer two
pins connect to zero and negative power lines respectively~ithin
body and to respective sides of the rocker switches.
In detail, the outer pins connect to printed circuit
strips 7 which extend below the respective sides of
the rocker switches and carry domed switching mom-
biers 8 to be actuated by the rockers to make a con-
section between one or other of strips 7 and Dyne of
four lines associated with respective switches. These
four lines are connected to four of the remaining
six pins 6, depending upon the function desired for
each rocker switch.
Before considering the circuitry of the trays-
miller various features will be described.
One feature is an option which can be selected to give momentary On or momentary Off control, ire.
a module will turn 'ON' when the key is pressed, and
turn 'OFF' when the key is released, or vice versa.
This feature is particularly useful when interfacing
to a remote sensor when designe~-to ye plunge into the socket 12.
which the keyboard section normally plugs into, i.e.
it can be arranged that the transmitter sends the
code to turn on a heater when a thermostat (which is
plugged into the micro-controller) closes and sends
I
8.
the code to -turn off the heater when the thermostat
opens.
US Patent l,59~,971 describes trays-
millers which send a one millisecond burst of data
immediately after each zero crossing, for use in 3-phase circuit. It can be shown, however, that
there is a 30 phase difference between 120V and
208V and between 120V and 277V in the USE, There-
Gore a one millisecond burst of data coupled from
the 120V line to the 208V or 277V line will not over-
lap the zero crossing of the 208V or 277V line. 208V
and 277V slave units or receivers, therefore, cannot
be controlled from existing transmitters without
using a repeater/coupler which is designed to receive
a signal from the 120V phases and retransmit it onto
the 208V or 277V phases, retimed so as to coincide
with the correct zero crossing.
The present embodiment, however, contains an
option which allows it to send data over the full
half cycle of the mains (instead of a one millisecond
burst). The signal will therefore overlap the zero
crossing points of the 208V or 277V lines. This,
therefore, eliminates the need fox a repeater in
systems which only use such transmitters,
The present embodiment also allows the user
to press keys simultaneously and if keys 1-ON, 2-ON,
3-ON, 4-ON were pressed, the digital control signal
code actually sent would define:- 1, 2, 3, 4, ON.
This cuts down transmission time and allows group
dimming. The reason why group dimming is possible
is that all receiver modules (slave units) will remain
addressed until reset by any number which follows a
function or command. Thus, signals 2, 3, 4, ON
would switch on units 1 to 4 and if that signal is
then followed by a command 'DOW', any dimming circuits
in units 1 to 4 would operate.
A further feature of this new transmitter is
its ability to continuously monitor the power main
for digital control signals (or noise) and hold back
any transmissions until the main is free. Even if
several such transmitters have had keys pressed
while another was transmitting, and are therefore
waiting to transmit, they will not all try to trays-
mix together. All such transmitters are synchrony
iced by any data on the line, and contain a self
polling system (determined by the selector switch
2), so that no two transmitters with different
selector switch settings on any one phase will inter-
lore with each other, and even transmitters with the
same selector switch setting will not interfere if
on different phases.
This self synchronizing interrupt facility Sian important feature for any control system which has
multiple controllers accessing data onto a single
wire pair, and has applications outside domestic
electrical appliance control systems.
Returning now to details of construction of
the transmitter, Figure 2 shows that the main body 4
includes a further rotary selector switch 9 by which
one can set a specific house code, corresponding to
the house code set at the slave units.
Within the main body 4 are two printed air-
cult boards Andy Asian in Figures 3 and 4.
The board 10 carries the fixed contacts of
house code and switch code selectors 2 and 3, an
eight way connector 12 for pins 6, components C7,
C8, C9 and RFC2 ion use in generating the 120KHz
carrier and an integrated circuit 11 (shown in
Figure 5). Options mentioned above are selected by
links Lo, Lo and Lo.
10 .
The board l~aprovides diodes DO, Do end Do
for creating the supply voltages ODD (-Ye) and VSS
(Ox) for -the circuitry. Also provided are coupon-
ens, including transistors Try and TRY and transform-
or TCl, or injecting 120KHz digital control signals from circuit 11 onto the mains and for receiving
signals from the mains at Lo, Lo. From mains line
Lo is obtained a voltage TRIG fed to circuit 11 for
the detection of mains zero-crossings.
Turning now to Figure 5, seven key sensing
blocks A to G are provided, connected to key con-
sections Al to I Clue, KF2 and KID. In the example
shown in Figure 3, KF2 is left unconnected and is
thus unused in this example, but could be connected
so that its block F replaces one other of the blocks.
Of the six blocks then available four are used at
any one time ! depending upon which keyboard section
is plugged into the main body.
Blocks Al to K4 are all used for entering
Number On/Number Off functions, i.e. for issuing
codes comprising addresses together with an 'ON'
or 'OF' commando Block Al is used for entering the
ON/OFF command for the first device number in a
sequence of four K2 is used for the second device
number and so on for K3 and K4. The blocks A to
are identical, so only block A is shown in detail.
Referring to block A, the key connection or input
Al normally sits at a voltage of VDD/2, This volt-
age is too low to turn on OR gate 57 via its high
threshold path Hit, and too high to urn off the OR
gate via its low -threshold path Lot, A switch
closure to either supply rail will give a '1' from
OR gate 57 which is then denounced by denounce logic
30 and provides a pulse (TIC) - another pulse, TED
is produced when Al is OPENED, but assume for the
~%~
if .
moment that input OVA is floating so that TED is
not enabled and will be ignored. use after PI
D-type bistable circuit 58 is clocked via delay
circuit 51 and if K1 was closed to OVA the output
Q of D-type bistable circuit 53 will be a '1'; this
will allow TIC to set an 'ON' bistable circuit 5
(via guts Andy). If K1 was closed to ODD, the
Q output of circuit 58 would be '0', setting 'OFF'
bistable 62 (via gates 63 and I). Block A therefore
recognizes a switch closure to OX to represent, ON"
(ire, address number 1 and command ON and a switch
closure to ODD to represent "1, OFF". Similarly
block B reeognises a switch closure to OX to repro-
sent "2, ON" and a switch closure to ODD to repros-
en "2, OFF". Likewise or blocks C and D tire.
ON, OFF functions for keys K3 and K4).
Blocks E, F and G are provided to issue commands
only, ire, corl~ands which apply to all, or groups of,
slave units designed to respond to those commands
(assuming, as always, that the house code associated
with the command is the correct one Block E gives
an "All lights on" command for a closure to OX and
an "All units off" command for a closure to ODD.
Block F gives an "All lights on" command for an OX
I closure and an "All lights off" command for a ODD
closure.
Now, if OVA pin is tied to OVA TED is enabled
and so therefore are gates Andy 66. This has the
effect that the bistable circuit 59 or 62 clocked on
opening switch K1, is the opposite to that docked
on closing K1, i.e. if closing K1 to OX represents
"1, ON", opening K1 from OX represents "1, OFF",
And if closing K1 to ODD represents "1, OFF", open-
in K1 from ODD represents "1, ON". Similarly blocks
B, C and D give momentary 'ON' control when closing
1 '. .
and opening K2, K3 or K4 -to and from OX, and moment-
cry 'OFF' control when closing and opening K2, K3
or K4 to and from ODD. Block E will signal "All
lights on" for closure to OX and "All units of"
when KFl is opened from OVA and "All units off" for
closure to ODD and "All lights on" when opened from
ODD. Block F will signal "All lights on" when KF2
is closed to OX and "All lights off" when KF2 is
opened from OVA and "All lights off" for closure to
ODD and "All lights on" when opened from ODD.
Input KID, block 'G' and its associated de-
bounce circuitry signals a closure to OX to provide
a 'Bright' command and a closure to ODD to provide
a 'Dim' command. This circuitry is unaffected by
OPAL
The fourteen possible "number, ON/OFF" out-
puts and function outputs (All lights on, All units
off, All lights off, Bright and Dim), are fed to
fourteen (only six shown) 3-input gates I whose outlets go to
a 14-input OR gate 6?, which enables gate 53 which
passes a clock signal to a 14-bit recirculating shift
register 19 (Fig. pa). This register has a '1' circulating
through it, a '1' being fed back in-to it by gate I
when all its outputs To to To are 'O'. The outputs
of the register serve to enable each input AND
gate 52 in turn (looking to see if any key has been
pressed). Signals "OFF EN " (Off enable), IRON EN"
(On enable), and "FUNCTION EN" (Function enable) are
all at '1' at this time, enabling the RAND gates 52.
Therefore, if any key is pressed, the output of the
gate I goes high and stops the clock to the register
19, with one of the outputs To to T14 then being a
'1'. If one of outputs To to To (associated with
blocks A to D) is a '1', this is decoded by OR gates
13, 14, 15 and 16, whose outputs address a 1 of
I
13.
block decoder 54 This block decoder 54, together
with a 1 of 16 decoder 55 address a 256 bit rum 56.
This 1 o-f 16 decoder is addressed by the 4 bits of
the address selector switch 2 of Figure 2. The out-
puts of gates 13, 14, 15 and 16 represent K1 ('ON'
or 'OFF'), Cowan' or 'Off'), K3 and K4 etc., rest
pectively, and the contents of the 256 bit rum are
such that if the selector switch is set to the
binary equivalent of decimal 1, the output of the
block decoder will be the binary equivalent of deal-
met 1 for To, decimal 2 for To, 3 for To and 4 for To
(i.e. keys K1 to K4 correspond to numbers 1 to 4).
If the selector switch is set to the binary equip-
alert of decimal 2, then the outputs of the block
decoder will correspond to 2, 3, and 5 for To, To,
To and To and so on, ire the selector switch and
the 256 bit rum allow the four input keys to select
any of 16 codes in groups of 4 consecutive numbers,
dependent on the setting of the selector switch.
It, however, one of the outputs To to T14 is
a '1' (instead of To to To) this represents a lung-
lion only ("all lights on", "All lights off", "All
units off", "Bright or "Dim"), and is decoded by a
function decoder 26. The outputs of the function
decoder are "Orbed" with the outputs of the block
decoder and applied to five of the preset inputs
of a 9-stage recirculating shift register 20, (the
other four inputs are connected to the house code
selector switch). The code representing the key
pressed, together with the selected House Code, is
loaded into the shift register by a signal (To +
TO) from a gate 17. Gate 18 will generate a TO
signal when signal COOK from gate 67 is obtained
(i.e. a key has been pressed) together with signal
BUSY being a '1' (not transmitting) and together
1'1 .
with signal TON being a '1' no other transmitter
is transmitting). If the key that was pressed was
a function (To to T14), then this function will be
loaded into the 9-bit shift register, TO will no-
set whichever input logic (blocks A to F) had generated
Coequal arc as more than one key may have been pressed,
the recirculating register 19 may now continue to look
for another coincidence.
If the next coincidence found indicates that
a "number, ON OF key was pressed, (To to T8j, then
the number will be loaded into register 20 by TO,
and one of the inputs to gates 21 and 22 will be
a '1'. If a "Number, ON" key was pressed (To, To,
To, To), gate 21 will reset a bistable circuit 23,
This will make "OFF EN" and "FUNCTION EN" a 'O';
therefore the recirculating register 19 will only
look for further "Number, On" key presses, (keys
may be pressed simultaneously so there may be up to
four "Number-On" coincidences. Each such number
code is shifted into and then out from register 20
in turn and transmitted in the same fashion as desk
cried in the above-mentioned patent.
If a "Number, Off" key was pressed, gate 22
will reset bistable circuit Sue that recirculating
register 19 will only look for further "Number-Off"
key presses. Aster transmitting all "Number-On"
numbers or all "Number-Off" numbers, it is required
to transmit "ON" or "OFF". Yen bistable 23 or 24
was reset, "FUNCTION EN" went to a '0' and one input
of gate 25 went to a '1'; therefore when all numbers
have been transmitted (Conical and BUSY), TO is pro-
duped and the junction decode block 26 applies either
the "ON" or the "OFF" code to register 20 and this
is loaded by TO (via gate 17).
It is therefore evident that if keys "l-ON",
"2-ON", "3-ON" and "4-ON" are pressed simultaneously
(or within 200 milliseconds of each other the codes
actually transmitted will be "1, I, 3, 4, ON", This
cuts down transmission time and allows "Group Dimming"
5 as all four slave units will remain addressed once
so activated,
The transmission circuitry has been discussed
in the above-mentioned patent, In summary, a state
counter 27 controls when the data is shifted out from
register 20 (gate 28), ire, no 'Clock' signal in
States 0-3 and State 4 (Start Code Insertion) and no
'Clock' signals in even states, ire, 2 (complement
data). In States O - 3, 120 HUT is grated to the
serial output (gate 29) and in State the output is
disabled (gate 30); therefore code 1110 is produced
(start code) in States 0 to I, In Odd states (2j
true data is grated to the output (gate 31) and in
even states 2, complement data is grated through
gates 32 and 33, The output signal envelope is gent
crated by a timing decoder 34 with option input OPB1
(at gate 35) selecting either three one millisecond
bursts (as with the above-mentioned patent, or one
burst encompassing a full half cycle, If option input
OPB2 is held at a '1', Q32 of the state counter 27
will be held at a '1' and as this so applied to bit
stable circuit 36, a-t the end of State 22 (decoded by
gate 37), END will be set which will stop the trays-
mission (gate 30), ire, only one complete code is
sent, If, however, OPB2 is a '0', the sixth stage
of the state counter will have Q = 'O' which will
prevent END from being set; therefore the whole code
will be transmitted again, The second time round,
however, the sixth stage of -the state counter will
have toggled and so END will be set, stopping the
transmission, Codes are thus transmitted Tess,
16.
BUSY is not reset until State 6 (bistable 38) which has the effect
of inserting zero's in the first six mains half cycles following the
end of a transmission, These options are chosen using links Lo and
Lo at instate input OPB1 and 2 (Figure 3). with no links, a single
message with 3 one millisecond bursts is produced; with link Lo, a
double transmission is produced with 3 one millisecond bursts; and
with link Lo, a single message is produced for one half-cycle,
A six stage binary counter 39 monitors the
mains during signal envelope time, looking for signals
from other transmitters or noise of a frequency which
could lock out a transmission. For this purpose
the recurrent one millisecond envelope signal EN
is used. A one millisecond burst of signal is recog-
nosed by a decode of 63 which sets bistable 40 and
I removes transmit enable (THEN) from gate 18 prevent-
in any transmission while a signal from another
transmitter is on the line. All transmitters in a
system therefore will be prevented from transmitting
whilst another transmitter has the line. A decode
of 63 means that a signal (or noise) is detected with
a frequency of at least 64KHz. The transmitter which
has the line, however, has "BUSY" set, which sets
bistable circuit 41 to produce "ENGAGED" and locks
out 'DECODE 63' and prevents bistable circuit 40
I from being set, At the end of transmission, the
state counter 27 will be at State 22. All other
transmitters in the system, however, vowel have had
their state counter set to 31 by "DECODE 63". There-
fore, on the next state, all transmitters in a system
will have their state counters synchronized a-t State
1. On State 8, bistable 40 is reset taking signal
Lo to a 'O', but if several transmitters had been
waiting to transmit it would not be desirable for
them all to try to transmit at State 1. Therefore, each trays-
I miller in a system will not get a signal "THEN" until the output of the state counter coincides with the setting of the selector
switch (signal "oOINC2"), ire, at the end of transmission all
17.
other transmitters are at State 31. All trays-
millers are synchronized and when State 8 is reached
bistable circuit 40 is reset on all transmitters,
The state counter keeps counting and if on a paretic-
ular transmitter the-selector switch is set Tess,
3, the state counter will count 9, lo, if, 12, 13,
14, 15,l, 2, 3, at which time "KINK" will go to a
'l', giving a 'l' at the output of gate 42 which will
produce a TOTS resetting the state counter to
lo State l and starting the transmission, This trays-
mission will reset all other transmitters to State
31 again, and at the end of this transmission if
another transmitter has its selector switch set to
say 5, then its state counter will count to State 5
at which time "KINK" will be produced and the
transmitter will be able to take the line.
Finally, it is noted that there is a zero crossing
detector 57 for producing a signal TRIG' at the mains
zero crossings for controlling the timing of various
of the functions set out above.
