level translator for mobile phones
Hi,
If I use a level translator as you suggested I think that I have to place two of them because real RS232 levels are inverted, I mean the logical zero is from +5V to +12V and the logical one is from -5V to -12 V. What do you think can I use a simple resistor divider from the TX pin of a 5V microcontroller and in the other direction I dont use any glue logic but just connect the TX from the mobile to the RX of the microcontroller. I think that the logical "one" treshold of the 8051 for instance Atmel will correctly intepret the logical level? But, many data cables for mobile phones when communicating with PC-s just use a simple MAX232(5V operated) so what is the point of correctly matching the voltage levels if it works without the matching?
Regards.