Quote:
Originally Posted by rogerg
So I agree with Monte, "quirky". I would suggest best avoided if possible.
Roger.
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Hi Roger,
Thanks for the post.
These days. most new laptops and many desktop machines only come with
USB ports. So for users of these systems who wish to interface to an RS-232
serial device, a USB Serial Adapter is still the recommended choice and can
provide a extremely reliable solution - provided one starts with the right adapter.
A good adapter is a combination of good hardware and just as importantly,
a good software driver.
Part of the legacy of the Windows operating system is a set of services and
interfaces known as the Windows Driver Model, or WDM. The WDM provides
certain unique challenges to driver writers and the bottom line is that not
all vendors appear to get it right.
What typifies serial communications in most amateur astronomy applications
are protocols that only transfer a small number of bytes back and forth at a time.
Whereas RS-232 was optimized for byte oriented transfers, USB was optimized
for bulk data transfers. Sometimes a poorly written USB Serial driver will work perfectly
well when transferring bulk data to a peripheral, but fail when performing byte
oriented transfers.
So any "quirkiness" really only applies to specific products out there, even
though there are no shortage of examples of them. However, truly reliable
solutions do exist and there is no need to avoid using a USB Serial Adapter
as long as one makes a prudent choice.
Best Regards
Gary Kopff
Wildcard Innovations Pty Ltd