John Rumm wrote:

I remember phoning round the multi serial card manufacturers a few
years ago, trying to find one that would support 75 bps for use with
older radio modems. It completely threw them off their sales pitch
having someone not interested in how fast it could go, but how slow ;-)


That's nowt - try looking for 45.45bps support :-)

Apparently the limitation is the number of clock divider stages in the
UARTs. When they increase the clock speed to support higher data rates,
they don't have enough dividers to get below 300bps.


--
Ian White