Newbie Questions

Punkychan · Post by **Punkychan** » Thu Aug 19, 2004 8:56 pm

Hello..a newbie here..
First of all I've got some (maybe stupid ot funny ) questions.My MX 422 is only on the way and seems that I can't wait to go head with my project, I'd like to know about connections of the LCD module.It's usb , so is it self powered ? or do I have to connect to some sort of power supply.I don't intend to connect any fans ot whatsoever, just that modules and maybe later would like to connect some LEDs as indicators.Can I connect those leds directly to the gpos or do I need a resisstor ?If I do have to connect the module to some kind of powers supply, where do I connect it ? The 12V 4 pin molex or the floppy power supply ? Sorry to ask this stupid question but I don't want to ' burn' my lcd...can't wait for it to arrive.Thanks.

Tyler · Post by **Tyler** » Thu Aug 19, 2004 11:57 pm

well as far as i know but dont quote me on this. your usb supplys yoru power form your computer. as for the otehr questions you will have to wait for henry miles or tom to reply to this post. hope thats helps

Tom · Post by **Tom** » Fri Aug 20, 2004 12:01 am

Good news for you!!!

You don't have to use any external power unless you want to run the high power GPOs. The LCD is powered through the USB cable. Just make sure you installed your drivers properly, and it will work fine. As for your LEDs, there are headers specially made for LEDs, and it's as easy as just connecting them up without any resistors. You can mount the LEDs on your computer case too, so they make your case look even nicer. The LED's are found at the link below. If you have anymore questions or concerns, please feel free to ask.

http://www.matrixorbital.com/pages/acce ... sp?CatID=2

Punkychan · Post by **Punkychan** » Fri Aug 20, 2004 2:57 am

Thanks...I'll start working for the templates right away.And whenit's ready and arrived I'll post some pics..

Johnny · Post by **Johnny** » Fri Aug 20, 2004 3:29 am

Quick question that might be important. I dont know this product but i assume its the same or very similar in respect of GPOs to the MX222?

Is it not true that only GPOs 4,5,6 (low powered) have resistance and allow direct connection of LEDs as the resistance is already in place? and 1,2,3 have no resistance? I'm thinking this because if this product is the same as the MX222, if he connects his LEDs to GPOs 1,2 or 3, even at 5V, will it eventually damage the LED? assuming these are standard 3.3V LEDs?

Punkychan · Post by **Punkychan** » Fri Aug 20, 2004 4:58 am

Yeah, agree with you...that worries me......reply please....

Miles · Post by **Miles** » Fri Aug 20, 2004 9:26 am

The MX422 actually has 4 high powered GPO's rather than 3 compared to that of the MX222. Therefore on the MX422, the low powered GPO's are labeled as GPO 5,6,7. You can still use the LED Indicator, as the connection is the same but the GPO numbers are different. If you were to use the high powered GPO's to be configured for low powered GPO's, you must have a current limiting resistor for your LED's. Depending on the LED's you use, your current limiting resistor value needs to be calculated.

Punkychan · Post by **Punkychan** » Fri Aug 20, 2004 8:55 pm

Great !! Thanks for the quick reply...gotta start workin......