At 17:36 98.03.12 -0600, you wrote:
>Hello,
>        I am a little confused about the bit time for RS232.
>My understanding is that the period is 104 microseconds and
>it looks like this:
>
>________             ________               ___________>
>              |            |             |              |
>              | 104us  |  104us   |  104us   | ......>  Repeat 10
>times ( 1 Start, 8 data, 1 stop)
>              I_______I             I________I
>           Start bit         bit1         bit 2 .........>
>
>I may have the polarity of the start bit wrong, I'm not sure if it
>goes low or high.
>
>
>James & Ili
>Irving, TX. 75038
>



Well, since the idle state of the line is high the start bit must be low.
About the bit time, it depends on the baud rate you are using. For instance
if you use 9600 then you must fit 9600 bits in one second so bit_time =
1/baud_rate = 104.167 uS (if you intend to use 4800 baud them the bit time
will double and so on).

        Jorge F
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cumprimentos / best regards
      Jorge Ferreira          mailto://jorgegf@mail.telepac.pt
------ Make sure brain is in gear before engaging mouth -------
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