Hello,

For those of you who emailed me reagrding my earlier thread, thank you. I spent all day and found many power AT supplies but no cases to put them in.

So....

Can anyone tell me if it is possible to place jumpers on a ATX power supply so that it will function WITHOUT A MOTHERBOARD?

My team is building (I am financing this) several Hallowen animatronics for our senior project. We were required to program automation using PLC's so I might as well have something to enjoy if I have to spend money, others on the team do not want to spemd much money so they were happy with my idea. I was born the night before Halloween.

My part is to come up with Stereo Sound Effects so I need CD quality sound (least expensive CD players that I can solder/modify are computer cdroms). So now I must find Tower Cases that can hold 5 to 6 CDROMs each to power the CDROMs, without having mother boards in case. I will build and install my own relay circuit board to interface the CDROMs with my PLC's (programmable controllers).

Thanks again for everyones help.

Ron

Two quick questions......why so many CD=ROMS?

And if you are just using the drives, why does it have to be a computer power supply. The roms need 5V and 12V...why not just make a power supply to give them what they need and not worry about the ATX supply?

Originally posted by rondotcom

Can anyone tell me if it is possible to place jumpers on a ATX power supply so that it will function WITHOUT A MOTHERBOARD?
http://www.thetechboard.com/tutorials/atx.php

One thing to beware of - some PSUs have a minimum current rating. This means that EACH output MUST be loaded to this minimum current, otherwise it can cause a complete PSU failure! If you are using only the 5 and 12 volt rails, the other rails need a resistive load. I know, it happened to me :mad:

David

I'm sorry that I can't help but i'd really appreciate a little explanation of how to interface the cdroms to a PLC, the power part I can understand but how do you "talk" to them, since a PLC doesn 't have IDE capabilities???(I have worked with plc's but I'm certainly no expert).
Thanx for any info,
Ludwig

Hi Ludwig,

I am not using them as computer CDROMs. I am using them just like regular CD players. I am only using ATX power supply to power the units. Computer CDroms have physical push buttons on front. I take the unit apart and solder wires to the push buttons at the PCB. My PLC's drive small 24 VDC relays with gold plated contacts. The relay contacts are jumped around the CDrom physical switches. I energize an output, the relay contact closes and I have just pressed the front panel push button. The particular CDROM I am using is by Creative Labs... The 1st button on front is PLAY/SKIP track (dual mode). If not plaing then button acts as PLAY, if playing then acts as SKIP TRACK. Second button is PAUSE/EJECT. If playing and press then it PAUSES (pressing play after pausing starts from EXACT place I paused it at) If NOT PLAYING then acts as EJECT.

Most CDROMs do not have PAUSE, they have STOP, which would make my logic writing more complicated.

Sequence is

1) Eject CDROM Tray (know start will be track 0 by doing this).
2) PLAY, which will close CDROM tray and start playing track 1 (which is silence).
3) I wait for 7 seconds so I know I have reached track 1 and then use SKIP button to pick track I want to PAUSE on.
4) At exact moment i need sound effect I simply hit PLAY again and sound effect plays.
5) Once complete I pause CDROM.

This way I can repeat sequence above (since paused when I press PAUSE/EJECT step 1) unit will Eject CDROM Tray.

It should be noted that CDROMS do power down after about 180 seconds so I must make sure not to hit PLAY (step 2) to early.

have a great day!!!

hmm