I have decided to use for my sms controller 16F84 PIC .Is it difficult to program this PIC? Can i connect it directly to mobile phone with out using any signal conversion IC like max 232? I will use siemens mobile.
PIC devices are not hard to program as the actual device programming goes.
IF you meant are PICs hard to use that is also no.
Im pretty sure you wont be able to connect to your phone directly without either writing the code to manage the proper signalling protcol or using a seperate transceiver device.