'IOError: [Errno 5] input / output error' using SMBus for analog reading via RPi


I have been looking for the answer for the error mentioned in the title but for the first time i haavent got an answer yet. We ll im trying to make my Raspberry pi read analog data but when i run the code in terminal window it gives me 'IOError: [Errno 5] Input/output error'.

The code im using to read analog data is shown below. Im using PCF8591 ADC converter.

from smbus import SMBus

bus = SMBus(0)

print "read a/d press ctrl + c to stop"

bus.write_byte(0x48, 0)
lastval = -1

while True:
  reada = bus.read_byte(0x48)
  if(abs(lastval-reada) > 2):

I understand it might be because of the version changed in raspberry pi and i should change SMBus(0) to SMBus(1). For this i checked my RPi version which is not the revised one. But still I tried to run the program by changing the SMBus number, still no luck with it.

The error I get is shown below:

Traceback (most recent call last):
  File "analogread.py", line 7, in <module>
    bus.write_byte(0x48, 0)
IOError: [Errno 5] Input/output error

Any help is appreciated. This is the basic block in my bigger project which im trying to execute. So, the fas thinster i get thing working the better i can build my application. Thank you

The cause to this might be that you're working remotely (SSH). After you disconnect the remote session, your program is still working and could try to print or interact to console, which is not available any more. This is what happened to me.