Re: Software for an older Mac Modem

[CUTblakeney@home.com (Jeff Blakeney)]

On 22 Sep 1999 12:37:08 GMT, supertimer@aol.com (Supertimer) wrote:

>Actually, I'm pretty sure that modem will work fine on
>the IIGS.  The IIGS uses the same serial chip and serial
>connectors as the Mac, so the serial ports will go up to
>56k normal serial or 230k AppleTalk.

The normal serial port asynchronous rate is 57,600 bps or 57.6 kbps,
not 56k.  The maximum asynchronous rate of modems is 56,600 bps or
56.6 kbps.

The synchronous rate used for AppleTalk is 230,400 bps or 230.4 kbps.

Just a little nit pick as I've seen you say this many times.  :-)

>ProTERM will handle it.  You'll want to set port speed
>to at least 38400 although 19200 might be sufficient for
>most compressed files (non compressed files are
>compressed by the modem and might need the extra
>port speed).  I think there is actually a "Practical
>Peripherals 14.4" setting in ProTERM.  If not, use
>"Generic Hayes 14.4" or something similar.

To get the maximum use out of the modem, it is best to set the port
speed to 57.6 kbps.  Using v.42bis compression, it is possible to get
up to four times compression on data being transferred.  This means
that a 14.4 kbps modem can transfer data at up to 57.6 kbps.  Using a
slower port rate may make the sending modem have to pause to wait for
the receiving modem to transfer its received data to your machine.

v.42bis is also smart enough not make already compressed data larger
than the original and often will still compress ShrinkIt files a
little more so you always end up with transfers over 1440 cps.

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