Max232 to convert non-standard rs232 signal to TTL?

Discussion in 'General Electronics Chat' started by jeff77789, Apr 2, 2013.

  1. jeff77789

    Thread Starter New Member

    Feb 22, 2013
    Today, 06:58 PM #1
    I actually have a MAX3232 that i bought from here:

    now i am also using a maxbotix MB1020 sensor in which it gives out an RS232 serial signal from the tx pin:

    When the *BW is open or held low, the TX output delivers
    asynchronous serial with an RS232 format, except voltages are 0-Vcc.
    The output is an ASCII capital “R”, followed by three ASCII character
    digits representing the range in inches up to a maximum of 255,
    followed by a carriage return (ASCII 13). The baud rate is 9600, 8
    bits, no parity, with one stop bit. Although the voltage of 0-Vcc is
    outside the RS232 standard, most RS232 devices have sufficient
    margin to read 0-Vcc serial data. If standard voltage level RS232 is
    desired, invert, and connect an RS232 converter such as a MAX232.
    When BW pin is held high the TX output sends a single pulse, suitable
    for low noise chaining. (no serial data).

    my understanding is that the signal is exactly inverted or opposite of TTL with the exception of voltage levels. basically 0v - 5v RS232

    so if i were to set up the MAX3232 to convert the RS232 to a TTL signal, what would i receive and would this be compatible with an arduino in the sense that it is still 0v - 5v?

    side question: what is a good thing to solder the MAX3232 onto if i dont have a PCB ...?
  2. MrChips


    Oct 2, 2009
    Just invert the signal with a common emitter NPN transistor circuit and feed this into the Arduino.