Date   : Fri, 01 Aug 2003 15:26:33 +0100
From   : Jon Ripley <beeb@...>
Subject: Re: Acceptable bounds of baud rate

In message <1059742990001707@...> you wrote:

> I meant to ask in my previous post, but forgot - has anyone ever tried
> to find out the margin of error allowed for tape baud rates by the BBC
> Micro and/or Electron ROM routines? Perhaps this is explicit from the
> BBC Micro hardware references? Anyone ever tried to see what the highest
> baud rate they could successfully load files at was?

In documentation the Electron is 1200 baud only and the BBC is 300/1200
baud. Not sure about what the actual limits are but the implemtation
surely must allow for tape players playing at slightly different speeds,
half dead batteries and tapes which have been stretched through use.
Otherwise most tapes probably would never load at all.

The reference manual says the BBC/Elk use the CUTS (Kansas City)
standard for 300 baud and a modified form of CUTS for 1200 baud.

One way to make programs load faster from tape was to put the reduce the
interblock gap (the high pitched tone between data blocks on the tape).
This could be reduced to almost no gap at all - a tenth of a second
instead of the default 2.5 seconds, this dramatically decreases the
loading/saving time of files.

HTH,
Jon R.
-- 
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