The screen does not turn on

i have a problem... it started a week ago... i was playing in my psp until the battery totally died... then i left it in my pocket... the next day.. i let it charge for 2 hours until the orange led turn off... i was ready to play again but when i wanted to turn it on the screen doesn't show anything... i only see the green led indicator light on... but neither the cd unit works... i guess its sw problem!? somebody has a program to recharge the firmware???