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Comment by alrs | Hacker News Reader

I could give two shits about the X1, but the new X260 can take 16GB of RAM and has an onboard ethernet port. Yes, please.

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The X220 takes 16GB, and an onboard gig-e Intel nic. It was released in 2011.

This. The X220 is still my day-to-day personal laptop, and I've yet to find anything else that's comparable (key feel, small size, durability, ease of service...)

X250 can't do 16GB, sadly.

You can get it directly from Lenovo.

X220 doesn't have a high resolution screen available, which is why I'm still stuck on an x200s.

> I could give two shits about the X1

The X1 comes with an (included) external ethernet dongle which runs at full speed. That is to say: it's not a BW-limited USB-based adapter.

I agree it's a bit silly to need a dongle, it seems to be quite a popular sacrifice (ref Macbook air) to help make laptops thinner.

As this trend increased, I suspect we will start seeing USB-C (3.x) type networking kits becoming the standard for ethernet. Maybe some day even without the RJ45 connector.

What about RS-232 and LPT?

I and most people in my job role carry usb -> DB9 rs232 dongles. doesn't work, of course, if you are trying to set up a serial console to debug the laptop, which is annoying, but it works fine for what we mostly use it for, which is to say, reading other serial consoles.

They're obsolete for consumer hardware and take up a lot of space, while a physical gigabit network port is extremely useful for low-latency high-throughput communication, such as to NAS.

(RS-232 is still somewhat useful for hobby embedded stuff, but everyone just buys FTDI clone USB-serial cables)

Unfortunately the FTDI stuff (really any USB<->UART converter) has latency issues in the embedded space. : \

I was wondering, would it be possible to create a better converter that did usb -> rs232/parallel port that had a special driver to put timing info? At least for driving CNC motors with a parallel port, timing is critical, you could send the pulse signal along with a timing, like 1 @ t0, 0 @ t0+1us etc.. Reading would be similar. The chip on the converter would have an accurate clock and faithfully reproduce the desired signal.

It could probably be done with isochronous mode (http://www.beyondlogic.org/usbnutshell/usb4.shtml#Isochronou...), but realistically it's easiest to just delegate all the real-time stuff to a $1 microcontroller on the other end of the USB link.

After having a quick look at all the external interfaces of my laptop, the only one that has a predictable latency (that I know of) is the microphone/headphone jack. It should be fairly trivial to convert a serial digital data to an audio signal that can be reverted back on the other end. Of course, initially the jack latency needs to be measured (e.g. using a loop connection) and accounted for.

RS-232 is also how you get PPS off your GPS for maximum clock accuracy. emulated RS-232 over USB wasn't good enough as of a couple years ago

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