Artwork not working

I built an artwork last summer using latching relays and mechanical trip wire switches but it was no very reliable so I have completely redesigned it around an arduino…but having spent hours and ££ I now cannot get it to work and it feels very disheartening.

Basically the scheme is as follows

pir sensor detects movement->
a short voice message is played through speaker ‘b’ and two leds flash inviting passers by to put a coin through a slot →

if a coin goes through the slot it triggers a switch →
a motor is turns on and rotates a wheel anticlockwise →
another short message plays saying thank you through speaker ‘a’ →
a lug on the rotating wheels knocks a switch →
after 4 second delay the motor stops →
end of sequence

so I can get the arduino to switch on and off the led lights

I have uploaded the code for the PIR, the output from the PIR seems permantnently on HIGH, unit isn’t working!

The SN754410 H bridge is wired up including a separate 12v supply for the motor…but whenever that is plugged in the chip gets extremely hot very quickly. I tried uploading the code to make the motor turn, activated by the coin through the slot: it doesn’t. Don’t know why. Is the chip now fried because it got hot, or is that normal. If it should not then what have I done wrong.

I simply cannot get my Arduino on my laptop to accept a sketch to try out the Wave shield…all I get is pages of error messages.

Right now, I feel like sticking the whole lot in the toaster. I have searched the forums and tried different things to resolve the various problems and got nowhere.

any advice welcome

Schematics and code, please. Also specs on the motor (voltage rating, stall/running current); the SN754410 only has the capability of 1 amp output, and that only with a heatsink (but it should go into thermal shutdown first, if you don't have a heatsink on it).

But before anyone can really help you, we need code, schematics, and specs...