16C550 UART running under Windows NT

[BrianG]

Hi folks,
(I don't normally cross-post, but I got no answers under the Comms/Signal Processing forum)

We have some ruggedised laptop computers which run a data file transfer application under Windows NT. These have unreliable performance over the RS422 serial interface port (running at 19.2k with a hard-wired link to the host device) caused by occasional lost characters. (We know the host device works fine when connected to the same application on a desktop PC)

We have seen the various Microsoft notes regarding FIFO problems with the older National 16550 and its "A" variants. We have also seen reports about devices from manufacturers other than National possibly not being 100% compatible with standard driver software.

My questions are:
1)any known bugs relating to later C-MOS versions as used in our laptops?
2)If you have you experienced this sort of problem: with what manufacturer and chip version?

Thanks in advance

 

[ScottyUK]

Brian,

Can I ask if this a Terralogic ruggedised laptop? We've just bought one with the RS-422 option and I'm asking in case it is something I need to watch out for.


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I don't suffer from insanity. I enjoy it...

 

[BrianG]

Hi Scotty,

No these are fairly old Raytheon "Chameleon" units. Not our choice, but something the customer already had and wanted to use.

P.S. - I saw your post earlier in the week about Win 3.11 etc., which is why I re-posted here. When we have reloaded the laptop with 3.11 it works just fine but we get no user security with that o/s (needed to stop tinkering and unauthorised software loading). This is the main reason we needed to use Win NT.

 

[ScottyUK]

Brian,

There is a 'virtual machine' emulator available for XP which allows some programs for the older O/S to be run from within XP. The port handling is ok, except for the occasions where A-B insist on replacing the OEM serial driver with their own driver for RS Linx and RS Logix. That doesn't work. Hell, it barely works in the native O/S.

I'm not sure if the old Raytheon will run XP at a tolerable speed, but there might be something similar for NT. I just got frustrated by A-B's drivers and set up the multi-boot option.

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I don't suffer from insanity. I enjoy it...