SWTPC 6800

william degnan billdegnan at gmail.com
Wed Aug 17 22:26:49 CDT 2016

> >
> > No doubt you can get it to work, and it can be a useful ability in some
> > situations.
> > But monitors and loaders tended to be written with different objectives.
> >
> > Monitors targetted interactive use, not receipt of back-to-back
> > which would be why you have to add per-char delays.
> > The monitor is likely dropping a character or starting a read in the
> > of one and getting garbage because it went away for too long while
> > up the command.
> > It only has the stop bit period, or even less time, to do processing
> > receipt of a character.
> >
> > Loaders expect back-to-back characters and are written or optimised
> > accordingly, not that one can't still run into problems, which is why
> > checksums can be good.

It would be a lot easier if everyone picked top or bottom posting when they
reply but I digress....

My suggestion to use the "monitor method" is a stop-gap just to get to the
point of loading in something useful when no other means was workinhg.  I
agree any process that has no checksum will be unreliable.  Whatever.. .
Let's say for now you have at least the monitor  method until something
better comes along.

As far as splitters for serial, they're plentiful on ebay...serial switch
boxes that is.  If you set your modern terminal sodtware to match the same
settings as the swtpc vintage terminal you would be able to switch between
them.  I sometimes load in programs using a modern terminal to download a
papertape into the computer then switch to a vintage terminal for use.
Simple...assuming you can get your modern machine to match the vintagr, and
you have the cables.  Otherwise you'll have to buy/make them.


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