Connect signal from IR-detector to 4 18M2 chips?

[Gunnar]

Hi! I`m using the standard IR-circuit as described on page 125, manual-2. I`ve connected the output from this circuit to 4 different 18M2. Each of these control a tubular 220V AC-motor via a driver transistor and mechanical relays. It works most of the time, but some time one or more motors doesn`t move when sending an IR-code. Should the circuit be changed if connecting in parallel to more than one chip?

I`ve had noise problems from switching on/off the motors, and this could maybe still be the problem. After fitting snubbers to the relay-outputs the noise seem to be gone, at least on the oscilloscope..

 

[hippy]

There seems little reason a single IR receiver and the standard circuit will not drive multiple PICAXE inputs so it could be an issue of motor interference.

Does everything work as expected when the relays are replaced by LED's and no mains switching is occurring ?

Perhaps post your circuit, circuits, layout, and any relevant information that might explain why there might be problems.

 

[Gunnar]

Thanks!
On each motor there is a quadrature encoder, which pulses is read by the picaxes. Without the pulses, the program won`t do much.
This is a controller for a home theater screen masking system. It`s been about a year since I built it. I also built a small version of the mechanical system that I used during programming. The motors and encoders are the same as will be used later on the full size system. I had to deal with a radon-problem in my theater-room, so the masking system has not yet been installed. And, of course I need to make it work properly.. I don`t have a complete schematic, but I post the circuit layout, in case you have the time to have a look There are two boards, the controller board has 4 18M2s. The circuits are the same for all 4. The encoder-pulses enter at the ENC1 - ENC4 connectors at the left. The Q1 to Q4 are just switches to turn off power to the encoders, to save some LED-life when the motors are not moving. The IR-signal is connected to pin 12 on all 4 18M2s. The right hand side is the power-supply (there is a 100uF in parallel to C6 not shown), a trigger-circuit that will turn on the controller when the projector is turned on, the connector for the IR-chip, and a output connector for connection to the relay-board.

IC-1 on the controller-board control the Q1 and Q2 relay-driver transistors on the relay board. Q1 will turn on or off the 220V voltage out of relay K1 (pin 5). Q2 select which of pin 4 or 5 on relay K2 will have 220V, turning the motor-1 CW or CCW. The RC-1 to RC-8 are RC-snubbers.

Comments are welcome

I`ll post some code later. I used a lookup-table that you suggested a year or to back for decoding the quadrature pulses

Controller board:

Relay-board:

 

[Gunnar]

I hooked up an oscope today to check one more time for spikes. i found some spikes on the relayboard, pin-1 on relay K1 and K2, but only when the endstop-switch in the motor was engaged. When starting/stopping the motor via relay K1 and K2 I see no spikes to speak of. The same with spikes on the encoder-pulses. I found no spikes on the 18M2 5V supply. So I`m now thinking that the hardware might be ok, and that I must look for the error in my code.. I`ll try to debug myself first.