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Computer with a real serial port

Posted: Fri Jan 12, 2018 3:46 pm
by Shiunbird
Gentlemen,

I'm desperate to get a computer with a real serial port (no stinky USB-Serial adapter). I have computers with serial ports, but none weighting less than 20kg.

When I was a teenager, I had a nice 12-inch Dell Latitude CPi A Series, Pentium II 300, two batteries, lovely machine. My sister ruined it, and I can't find one on eBay.

Any suggestions? I just need it to run any BSD or Linux to do some serial port debugging. I need to bypass handshaking and force data through specific pins, so I'm not being successful with USB-Serial converters.

Thanks as always.

Re: Computer with a real serial port

Posted: Fri Jan 12, 2018 5:34 pm
by Raion-Fox
Thinkpad A23

Re: Computer with a real serial port

Posted: Fri Jan 12, 2018 9:23 pm
by thunderbird32
I use an old monochrome 486 Dell Latitude as a kind of portable serial terminal, but that's not much help to you as you want to run Linux or BSD (I run DOS 6.22/Win 3.11 on mine). :lol:

I agree with Raion-Fox, an older ThinkPad would be good. Alternatively, if you have a newer laptop with an ExpressCard slot, they make ExpressCard serial cards. I would think, as ExpressCard is PCI-Express, it might work as well as a built-in port. I've been considering getting one for my daily-driver ThinkPad.

Re: Computer with a real serial port

Posted: Sat Jan 13, 2018 12:57 am
by uunix
I have two nice little 'SHUTTLE' boxes that come with real serial, very small base units. Can't recall the exact model, CPU is i3 with 16GB, SSD all of which I had to buy separately. They are mounted on my wall and I RDP into them, although you can use them directly with keyboard/mouse and they have two video outs, DVI & HDMI. Nice boxes.

Re: Computer with a real serial port

Posted: Sat Jan 13, 2018 3:53 am
by Trippynet
You can get PCMCIA cards for laptops that add proper hardware ports. I have a parallel port one for an old laptop of mine.

Or, the Dell Latitude D630 is a good bet. Core 2 Duo, can take 4GB of RAM and an SSD if required, runs Windows 7 fine (or whatever else you want), and has a proper serial port on the back (and it's a solidly built laptop too). We keep a couple of them at work for emergency console access to switches as it saves faffing on with USB to Serial adapters. I also have one at home for L1 access to my SGIs.

Re: Computer with a real serial port

Posted: Sat Jan 13, 2018 10:26 am
by josehill
Trippynet wrote:You can get PCMCIA cards for laptops that add proper hardware ports. I have a parallel port one for an old laptop of mine.

Or, the Dell Latitude D630 is a good bet. Core 2 Duo, can take 4GB of RAM and an SSD if required, runs Windows 7 fine (or whatever else you want), and has a proper serial port on the back (and it's a solidly built laptop too).


Agreed on both the PCMCIA option and the Latitude D630. A decade ago, large companies bought/leased Latitude D630 laptops by the truckload, so they're pretty easy to find, and, as Trippynet mentioned, they are solidly built. Not quite as solid as a good ThinkPad, but not bad at all. I just looked on eBay, and here in the US, there are quite a few available in the $50-$150 range.

I assume that you are looking for older (cheaper) solutions, but it's worth mentioning that you can buy new laptops with serial ports from major manufacturers. For example, here in the US, you can get a new HP ProBook 655 with RS-232 serial port and Win10 Pro for under $700. Order it with FreeDOS instead of Windows, and the price is just a little over $500. For a new machine, it's definitely no speed demon, but it's certainly adequate for general use, and you get a proper warranty. Hmm...Now that I'm looking at it, I might get one for myself! (There are serial-equipped ProBook models with i5 and i7 cpus, but then you are getting over $1k.)

Also interesting, but quite a bit pricier, are Dell's ruggedized Latitudes.

Re: Computer with a real serial port

Posted: Sat Jan 13, 2018 10:45 am
by Irinikus
Those Dell's are really cool!

I currently use an old HP Nx6120 with a Centrino CPU as my terminal laptop and it works fine for me. (Nice and neat)

I would love to have an old IBM Think-Pad, but that rubberised coating.......???

Re: Computer with a real serial port

Posted: Sat Jan 13, 2018 2:00 pm
by robespierre
Toughbooks also had real serial ports until a few years ago.

Re: Computer with a real serial port

Posted: Sat Jan 13, 2018 2:44 pm
by Shiunbird
Thanks for all the suggestions.

The Dell Latitude seems to be a good deal, although a bit too big. It costs next to nothing, though.
Brainfarting me has not thought of PCMCIA. I will see if I can get something that works with my PowerBook G4. If it does, I'm sorted. Otherwise, I'll probably check the Latitude.

I have no experience doing serious things with Windows, so I'd avoid the learning curve. My fingers were crossed for the super mini Sony Vaios (the ones with super high density 9 inch screens) to have serial ports, but nah. I almost considered picking up a Cassiopeia or a HP Jornada with Windows CE and putting Linux in them.

Re: Computer with a real serial port

Posted: Sat Jan 13, 2018 3:10 pm
by xiri
Another alternative is a cheap and boring Dell Optiplex 980 (2010-ish).
Those were built even with a core i7 and have a parallel port, a serial port and ps/2 ports besides 4 usb-ports.
They do not occupy a lot of space and are pretty silent machines as well.

Re: Computer with a real serial port

Posted: Sat Jan 13, 2018 8:07 pm
by guardian452
Panasonic cf-53/cf-54, 33, etc.

I like my cf-53 more every year and I'm thinking about getting a 33 to play with. Looks neat.

Unlike Lenovo they almost fully comply with the rs232 spec (as I found out with a T61).

Re: Computer with a real serial port

Posted: Sun Jan 14, 2018 11:44 am
by escimo
If not using my PCD-4H under Solaris 2.4 with "tip", probably the job will be done by my 11 year old IBM/Lenovo T60 runig Ubuntu 10.04LTS with an optional SER/PAR drive fitting into the CD/DVD drive bay/slot.

Re: Computer with a real serial port

Posted: Sun Jan 14, 2018 2:59 pm
by japes
xiri wrote:Another alternative is a cheap and boring Dell Optiplex 980 (2010-ish).
Those were built even with a core i7 and have a parallel port, a serial port and ps/2 ports besides 4 usb-ports.
They do not occupy a lot of space and are pretty silent machines as well.


If portable (laptop) isn't a requirement, yes, most of the business PCs even in their small form factor configs will offer a serial port, at least up until nearly recent times. So that lets you pick from Dell/Lenovo/HP...there's a local pc recycler to me that always has shelves of these retired from enterprise businesses.

Mini ITX would be another way to go if you want to piece something together.

Laptops you probably have to go back pretty far, or try PCMCIA/ExpressCard or different USB converters (I gave up on all the cheap ones and buy the FTDI ones now).

Re: Computer with a real serial port

Posted: Sun Jan 14, 2018 3:39 pm
by smj
Laptops are a good choice because you don't need to worry about space for a separate keyboard, monitor, etc.

But if you're looking for something less portable, I would suggest an old thin-client. They usually include one or two real serial ports, often a parallel port, USB, etc. You'll probably get serial terminal functionality out of the box, depending on which model you select, and many older examples are listed on eBay for under US$30. (HP T5735 w/ AC adapter: 1GHz AMD Sempron CPU, 1GB RAM, 1GB Flash, $22 shipped in US, eBay #382315642603 - no affiliation)

Almost all of them will boot your favorite Linux distro from a USB key with no fuss. If you want to install a complete OS for some reason, many can take an internal SSD or laptop drive - but most have adequate flash storage for a small bootable image, or just keep booting from a USB key.

Have a look at this site for details on many models, including Linux compatibility and expansion options: http://www.parkytowers.me.uk/thin/index.shtml.

Re: Computer with a real serial port

Posted: Sun Jan 14, 2018 8:36 pm
by robespierre
smj wrote:Have a look at this site for details on many models, including Linux compatibility and expansion options: http://www.parkytowers.me.uk/thin/index.shtml.

Good advice, and that site's a great resource.