No real arguments from me.
The RS-232 spec. (now EIA-232) is often referred to, but rarely actually read. Part of the reason for this is because EIA (Electronics Industries Alliance) does not make it particularly easy to get your hands on a copy of the bloody specification. You are welcome to purchase a copy from Global Engineering Documents for $100.00 (US) . Frankly, I would rather spend $100 on my various robotics projects.
I had a photocopy of a photocopy of the actual EIA-232 specification some number of years back and it was not terribly exciting. From my possibly foggy memory, EIA-232 specifies the voltages levels (+/- 12V) and the pin-outs for DCE (Data Communications Equipment) and DTE (Data Terminal equipment.) To first approximation DCE=modem and DTE=teletype. The pin-out outs are for 25-pin D connector. To the best of my recollection (I could be wrong) the spec. did not specify the asynchronous signalling protocol of a start bit, 7 or 8 data bits, optionial parity bit, and 1,
1.5, or 2 stop bits. I do not know if that is written down in a different spec. somewhere. I also remember that the maximum cable length was specified as around 50 feet, even though people regularly exceeded that specification.If anybody has the actual EIA-232 specification and can quote from it please feel free correct any errors in the text above.
-Wayne
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