Darn i messed up :/
I wanted to experiment a bit more with 2 digits displays. But i got myself a display HDSP-5523 from agilent technologies without thinking that i would not have enough power from USB to power it as a whole. So i wrote a program to test just single digit.
mBed standard pin output is 40mA and total current that is avaliable for peripherals from USB is 500mA. The microcontroller takes 100mA without Ethernet so that means 400mA is avaliable for other peripherals. The HDSP-5523 is a 16 LED segment 2 digits with 2 decimal dots. Each LED segment takes 30 mA optimal. If i would like to test the whole display i would require 480 mA of curent but i have just 400mA from the USB. Meaning im 80 mA short. On top of that i dont have enoug resistors to cut the standard pin output from 40 mA to 30. So this was a good lesson for me to make some callculations first and order things afterwards. Ah well i guess everybody have gone through this. Im thinking that next i will take some old nokia phone and take out the display, the keyboard, microphone, speaker and do some "magic" with thoose :) Hopefully i would be able to solder them out - if not atleast the keyboard and display would really help. Stay tuned =)
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