Sophie: howto-html-it-10.1-4mdv2008.1 noarch

howto-html-it-10.1-4mdv2008.1.noarch.rpm

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NAME="AEN745">12.1. A note about serial ports and speed capabilities</H1
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>If you are using a high speed (external) modem (14,400 Baud or above),
your serial port needs to be capable of handling the throughput that
such a modem is capable of producing, particularly when the modems are
compressing the data.</P
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>This requires your serial port to use a modern UART (Universal
Asynchronous Receiver Transmitter) such as a 16550(A). If you are using
an old machine (or old serial card), it is quite possible that your
serial port has only an 8250 UART, which will cause you considerable
problems when used with a high speed modem.</P
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>Use the command...

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>setserial -a /dev/ttySx</PRE
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>&#13;</P
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>to get Linux to report to you the type of UART you have. If you
do not have a 16550A type UART, invest in a new serial card (available
for under $50). When you purchase a new card, make sure you can
move the IRQs around on it!</P
><P
>Note: the first versions of the 16550 UART chip had an error. This was
rapidly discovered and a revision of the chip was released - the 16550A
UART. A relatively small number of the faulty chips did however get into
circulation. It is unlikely that you will encounter one of these but you
should look for a response that says 16550A, particularly on serial
cards of some vintage.</P
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