X-10 Data-Stream Monitor
Philip C. Plunkett
pplunkett@cix.co.uk
ABACUS ELECTRICS
10 Barley Mow Passage
Chiswick, London, W4 4PH, U.K.
Document Revision 1.01- January 2002
Source Code Revision 1.20 - August 1996
http://www.cix.co.uk/~pplunkett/x10.htm
Introduction
This document describes how the author’s X-10 compatible appliance module may be used as a simple
X-10 data-stream monitor. Raw X-10 data on the power-line is converted into RS232 data that may be
monitored on a PC running a terminal program. In fact the ‘monitor’ was designed before the
appliance module when it became necessary to fully understand the data format as generated by
various X-10 power-line controllers. This ‘earlier work’ is published now at the request of some
constructors. Hopefully it will also aid in analysing problems encountered when building the
appliance modules. It should be read in conjunction with the earlier design article (distributed as
X10AM1.ZIP).
Disclaimer
Construction of the X-10 power-line equipment should only be undertaken by an experienced
constructor with access to test equipment. In use and during test the circuits are connected directly to
the power-line and so danger is involved. The author accepts no liability for the health and safety of
the constructor assembling or modifying his designs.
Description
The data-stream monitor uses the same circuit board as the appliance module. The PIC16C54A
micro-controller contains a different program so that instead of interpreting the X-10 data and
switching a triac the PIC drives an opto-isolator with RS-232 data. The PIC16C54A does not interpret
the data in any way. At each power-line zero crossing either an ASCII ‘0’ or ‘1’ is transmitted to
indicate the absence or presence of the 120kHz carrier.
PC Software
The PC should run a terminal program set to the correct COM port, 4800 baud, and 8N1 format (eight
data bits, no parity, 1 stop bit). The author used Procomm+ for DOS however Windows
Hyperterminal could probably serve. Data pours out of the monitor so a terminal program that can
freeze the display or capture the data to a file for examination later is most useful.
1
PC Interface
On the author’s appliance modules the manual on/off switch is wired to the circuit board via a two-pin
connector. These two pins provide a simple connection point for the RS232 data output. The monitor
software in the PIC16C54A configures the RA3 port to be an output and drives the LED inside the
opto-isolator. The COM port TXD and DTR lines from the PC are used to power the opto-isolator
output circuit. As the PC only listens and does not transmit, the TXD line stays in the idle state and
acts as a negative supply. The DTR line is normally set positive when the PC opens the COM port. It
is used as a positive supply.
R10
U2
22k
1
RA1
RA3
RA0
17
3
RTCC
OSC1
16
4
R101
P101
9-pin Female 'D'
5
RXD
4
DTR
2
U101
4N25
14
6
RBO
RB7
13
RB1
RB6
RB2
RB5
RB3
RB4
9
On/Off
toggle
key
R102
15k
SW1
2
15
VDD
8
TXD
OSC2/CLKOUT
VSS (GND)
7
1
/MCLR
5
220
1
6
2
7
3
8
4
9
5
18
RA2
2
PIC16C54A
12
11
10
PIC Object Code
The object code is provided in two versions, the first for the PIC16C54A micro-controller and the
second for the PIC16F84A micro-controller
The object code below should first be cut and pasted into a text file called, for example,
X10DSM2.HEX and then programmed into a PIC16C54A micro-controller. The code sets the clock
to ‘XT’, the watchdog on, and code protection off.
:10000000060C0500FF0C0600050568006A006B0081
:100010006C006D006900070C0200480956093009A0
:100020000307140A18090E0A16090E0A300C190AD9
:10003000310C2F00080C2E0065052A092F03030739
:100040006505030665042A09EE021E0A65042A09ED
:100050002A090008320C29000000E9022C0A0008D5
:10006000380956094507360A030500080304000845
:1000700025063E0A040025073A0A00080400250662
:100080003E0A0008060C29004D0A0F0C29004D0AF3
:100090001E0C29004D0A3D0C2900C00C2100040053
:1000A000010243074F0AE9024D0A000861000400FB
:0800B00001024306570A000893
:0203FE00000AF3
:080400000A000B000A000C00C9
:021FFE00FD0FD5
:00000001FF
The object code below should first be cut and pasted into a text file called, for example,
X10DSMB1.HEX and then programmed into a PIC16F84A micro-controller. The code sets the clock
to ‘XT’, the watchdog on, and code protection off.
:1000000006306500FF3066000514900192019301EF
:10001000940195019101073062004820562030205C
:10002000031C142818200E2816200E2830301928FA
:10003000313097000830960085152A20970C031C54
:100040008515031885112A20960B1E2885112A2054
:100050002A200034323091000000910B2C2800340B
:1000600038205620051D36280314003403100034B0
:1000700085183E286400851C3A28003464008518E1
:100080003E280034063091004D280F3091004D2855
:100090001E3091004D283D309100C0308100640039
:1000A0000108031D4F28910B4D2800348101640085
:0800B000010803195728003470
:0203FE000028D5
:084000000A000B000A000C008D
:02400E00FD3F74
:00000001FF
3
PC Terminal Display
The power-line data-stream below was captured on a PC running Procomm Plus for DOS. A nearby
X-10 Mini-controller was used to generate the data by pressing in sequence, A1 on, A1 off, A2 on, A2
off, A1 on and then dim was held down for a few seconds.
00000000000000000000000000000000000000000000000000000000000000000000000000000000
00000000000000000000000000000000000011100110100101101001011110011010010110100101
00000011100110100101011001101110011010010101100110000000000000000000000000000000
00000000000000000000000000000000000000000000000000000000000000000000000000000000
00000000000000000000000000000000000000000000000000000000000000000000000000000000
00000000000000000000000000000000000000000000000000000000000000000000000000000000
00000000000000000000000000000000000000000000000000000000000000000000000000000000
00000000000000000000000111001101001011010010111100110100101101001010000001110011
01001010110101011100110100101011010100000000000000000000000000000000000000000000
00000000000000000000000000000000000000000000000000000000000000000000000000000000
00000000000000000000000000000000000000000000000000000000000000000000000000000000
00000000000000000000000000000000000000000000000000000000000000000000000000000000
00000000000000000000000000000000000000000000000000000000000000000000000000000000
00000000000000000000000000000000000000000011100110100110101001011110011010011010
10010100000011100110100101011001101110011010010101100110000000000000000000000000
00000000000000000000000000000000000000000000000000000000000000000000000000000000
00000000000000000000000000000000000000000000000000000000000000000000000000000000
00000000000000000000000000000000000000000000000000000000000000000000000000000000
00000000000000000000000000000000000000000000000000000000000000000000000000000000
00000000000000000000000000000000000000000000000000000000000000000000000000000000
00000000000000000000000000000000000000000000011100110100110101001011110011010011
01010010100000011110111100101011010101110011010010101101010000000000000000000000
00000000000000000000000000000000000000000000000000000000000000000000000000000000
00000000000000000000000000000000000000000000000000000000000000000000000000000000
00000000000000000000000000000000000000000000000000000000000000000000000000000000
00000000000000000000000000000000000000000000000000000000000000000000000000000000
00000000000000000000000000000000000000000000000000000000000000000000000000000000
00000000000000000000000000000000000000000000000000000000000000000000000000000000
00000000000000000000000000000000111001101001011010010111100110100101101001010000
00111001101001010110011011100110100101011001100000000000000000000000000000000000
00000000000000000000000000000000000000000000000000000000000000000000000000000000
00000000000000000000000000000000000000000000000000000000000000000000000000000000
00000000000000000000000000000000000000000000000000000000000000000000000000000000
00000000000000000000000000000000000000000000000000000000000000000000000000000000
00000000000000000000000000000000000000000000000000011100110100101100101101110011
01001011001011011100110100101100101101110011010010110010110111001101001011001011
01110011010010110010110111001101001011001011011100110100101100101101110011010010
11001011011100110100101100101101110011010010110010110111001101001011001011011100
11010010110010110111001101001011001011011100110100101100101101110011010010110010
11011100110100101100101101110011010010110010110111001101001011001011011100110100
10110010110111001101001011001011011100110100101100101101110011010010110010110111
00110100101100101101110011010010110010110111001101001011001011011100110100101100
10110111001101001011001011011100110100101100101101110011010010110010110111001101
00101100101101110011010010110010110111001101001011001011011100110100101100101101
11001101001011001011011100110100101100101100000000000000000000000000000000000000
00000000000000000000000000000000000000000000000000000000000000000000000000000000
00000000000000000000000000000000000000000000000000000000000000000000000000000000
4
A1 on
A1 off
A2 on
A2 off
A1 on
dim