Okay here is the thing, i am trying to use the Rx pin on the maxbotix ultrasonic sensor because it sends digital and that is the only type of signal that small & cheap rf transmitters can transmit (i am trying to transmit the signal wirelessly to a range of 20ft) http://www.maxbotix.com/documents/MB1030_Datasheet.pdf now, it says:
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).
i dont understand:
- what does an "asynchronous serial with rs232" mean?
- it says to invert the signal but i have no idea what i should do for that
- how would the stop bit affect the program?
i want a pure software approach to this and i am sure there is but the non-standard voltages and the inverted signal is killing me. i cannot get any hardware such as a MAX232
is there any example programs that i can go off of?
thanks everybody in advance