Author Topic: Motion Sensor (x10) causing "Bad checksum reveived"  (Read 2527 times)


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Motion Sensor (x10) causing "Bad checksum reveived"
« on: February 23, 2006, 03:06:37 pm »
Hi all,

Ive been working on this x10 problem for 2 weeks now, im running out of ideas so im turning to you. Sure hope you can help me solve this one.

Here's my simple x10 setup:

Pluto latest version ( if I remember correctly)
Core/Hybrid PC running Pluto
1xCM11A plugged to pluto core/hybrid pc.
1xRR501 tranceiver
1xMS16A Motion Sensor (compatible with RR501)
1xBasic Light on/off/dimmer module.

*My goal is to be able tu trigger actions (programmed in pluto events eg: turn on a light) when the motion sensor is triggered. Simple enough. (I want the Motion Sensors signals (off/on) to be used by pluto trough tranceiver and CM11A, NOT in a "stand alone" way. )

When there is no Motion Sensor in the setup, eveything works fine. I can control lights from my scenarios, it's great.

If I forget about the core/hybrid pc and the CM11A module plugged to it, and simply set my motion detector to A1, and my light module also to A1, everything works.  When movement is detected, lights turn on for 1 minute, then turns off (default setting for the motion detector / working in Stand Alone mode, no Pluto or CM11A involved).

The problem occurs when I try to make everything work together.
When CM11A controls the light switch, it works alright UNTIL I put the batteries in the motion sensor.  As soon as the motion sensor sends its first ON signal, everything stops working.   I found this (see below) in the CM11A logs, witch is most probably the source of my problem:
10 02/22/06 21:33:15.988  Got response: 5a from CM11A.
01 02/22/06 21:33:15.988  Bad checksum received (send:72,
10  02/22/06 21:33:16.088 Sending address with HouseCode=6,
10      02/22/06 21:33:16.088           Sending packet with HighByte=4,
10      02/22/06 21:33:16.088           Sending header with Checksum: 72.
10      02/22/06 21:33:17.828           Got response: 5a from CM11A.

These Bad Checksum start as soon as the motion sensor kicks in.
To make my scenario work again, I must take the batteries out of the motion sensor and unplug/replug the CM11A module.

Ive tried may different ways to configure this, including:

Tranceiver A1, Light Switch A2, motion detect A3 = Problem
Tranceiver A9, Light Switch A2, motion detect A3 = Problem
Tranceiver A1, Light Switch A2, motion detect B3 = No problem, but the motion detector seems to be ignored by the tranceiver (if Im right, the tranceiver only listens to A house code signals).

Ive tryed many many other things in the past 2 weeks.
Im pretty sure the hardware is fine beacause it works independently, but not together.

Any feedbacks would be apresheated.
(if anyone could tell me in whitch LOG should I check to see LIVE motion detected messages, that would be great. I havent found any...)

Thanks alot guys.
Can't wait to hear from you.
Keep up the good work at pluto.



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trying to answer my own question...
« Reply #1 on: February 24, 2006, 02:51:42 am »
Hi again...  I found this quote on a "X10 DEBUG" site.  
Has anyone experienced this problem?
If so, how can it be solved ?

Here's the quote:

"RF Transceiver Problems

X10 TM751 and RR501 RF transceivers are known to have an "endless dim" problem. In certain situations, they can repeatedly transmit X10 dim (or brighten) signals onto the power line, corrupting X10 transmissions from other devices. Another problem can occur if you have more than one of these devices. The TM751 does not monitor the AC line to see if it is colliding with X10 commands already being sent (the RR501 does monitor the line before starting a transmission). As a result, two or more transceivers could corrupt each other's signals. If you have such devices, disconnect them while troubleshooting other X10 problems."

NOTE:  I only have one tranceiver (RR501)

Thx alot for your help, im desperate.