On Thu, Dec 18, 2008 at 03:51:36PM +0000, Grant Edwards wrote: > Yes there are. The standard is that RTS is asserted when one > whishes to transmit (and de-asserted when one has finished > transmitting). Optionally, one waits for CTS to be asserted > before transmitting. Isn't that the definition of RTS and CTS > that's in the standard? There's a standard, which is not necessarily well adhered to. Heck, full-duplex RTS/CTS standard was used by thousands if not millions of modems in flagrent violation of the RS-232 standard for some 10 years or more before TIA-232-E was released and bowed to reality. I know I received all sorts of requests for very strange implementations of half-duplex, with people sending me product specs with all manner of requirements, both in terms of which RS-232 lines were used (which may have been confusions caused by the fact that many systems ship with random and wondrous DB9->DB25 cables, or strange DTE/DCE conversion cables), but also in terms of mutually exclusive requirements in terms of minimum and maximum turnaround times. Someday when I'm board I can try to dig the requests out of the archives, but I can definitely say that people asked for very strange things, much of which was not in the standard (and as I pointed out, until 1990 traditional full-duplex RTS/CTS hardware flow control was not recognized by the RS-232 standard either). - Ted -- To unsubscribe from this list: send the line "unsubscribe linux-serial" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
