Hi,I have a 4+1 Led display from microcockpit. Now, i've found some old 7 segment displays that i want to connect.If i look at the bluesideup site, it says to use current limiting resistors. But, on my 4+1display, no such resistor is used.I checked which 7seg display they use: HDSP-7501. When i look at the specs of this, http://www.segyung.co.kr/DN/AGILENT/HDSP-750X.pdf , it doesnt show a current limiting resistor.So i'm a little confused now, and i do NOT want to frie my expensive adored hardware :)Kind Regards,Highvolt

Hi!I had the same thoughts when I wired up my first 7 segment displays. I didn't used resistors and it also worked. In the datasheet of the ICM7218 that is used on the board it says that there will be at maximum 50mA drawn on each segment. So you can check the discription of your 7 segment displays and decide whether you need a resistor or not. Very convenient is to use the 7 segment display mounts from CSI (www.em.ca/~cockpits) otherwise you will go crazy when soldering!! :-)regards,steve ---------------------------------------------------------------------Do you know the A320 Flightdeck Project? Visit www.a320flightdeck.com

I got some experiment board from velleman that i can use.i'll ask microcockpit about this. i'll post the answer here too.Thanx for the info,Wim

Reply from microcockpitResistors are built in integrated circuit 7218CIJI located on the display controller.>>So, do I need resistors or not ?So, no. But be sure your 7-segment display can support about 15 mA for each segment.So, a big thanks goes to Thierry Magnan for his great support.