Monthly Archives: August 2008

Dot-Matrix Teletype Simulator Update and Request for Teletype Info

Hardware

I recently wrote about wanting to have a teletype. Well, I have since realized that teletypes weigh hundreds of pounds, draw hundreds of watts, and aren’t available on eBay for a reasonable price. Well I knew the hundreds of pounds bit, but still. I pretty well have had to give up on a real teletype.

So, now on to the next best thing: a teletype simulator. Enter the two free dot-matrix printers that found their way to my office earlier this week. One of them even works. I bicycled to the awesome local office supplies store (about 11 miles away) to buy a ribbon for it. This is the place that’s been there since the 1890s. They still stock dot matrix ribbons, typewriter ribbons, and even fanfold paper.

On the project. Linux has its heritage in Unix, which was used with these devices. It can be made to work with them even now. But there’s a trick: teletypes used a bidirectional serial link. Dot matrix printers have no keyboard. So we have to take input from a different device than we send output to.

A simple trick will do for that:

TERM=escpterm telnet localhost > /dev/lp0

Now, here’s the next problem. Dot-matrix printers have a line buffer. They don’t start printing the line at all until they see CR or LF. Makes it annoying for interactive use. So I wrote a quick tool to insert into that pipeline. After a certain timeout after the input stops, it will force the printer to flush its buffer. Took a little while to figure out how to do that, too; turns out there’s a command ESC J that takes an increment for vertical spacing in 1/216 inch, and accepts 0. So I can send \x1BJ\x00 to flush the buffer. I can run it like this:

TERM=escpterm telnet localhost | escpbuf > /dev/lp0

That leaves another problem, though: the printhead is right over the text. (Even though it moves to the right of the printing position, and then moves back left for the next character to print.) I modified the program to roll the paper out a bit, and then reverse feed it to continue printing the line. But that is slow and, I suspect, tough on the stepper motor.

Also, I have crafted a terminfo file for the Epson-compatible dot-matrix printers (which are almost all of them), which can also be found at the above link.

So here’s the question, for anyone that has used a real teletype:

Did the printhead obscure the text there too, or could you see the entire current line at all times?

From Dell, a Uniquely Terrible Experience

Hardware

Ah, Dell. Seeming inventors of the tech support pit of bureaucratic indifferences, inventors of the flamingo pink Inspiron, perpetrators of fraud in New York…

I have, for over a year now, been on a crusade trying to get them to stop sending me their Dell Home and Home Office catalog to my mailbox. It has been a bundle of fun, let me tell you.

They have a nice-sounding privacy policy. It says you can opt out of all their mailings by filling out a form online. Yeah, good luck with that. First of all, there are different forms for different departments at Dell. I’ve filled out them all, multiple times. They do nothing whatsoever. Perhaps they use them as lists of known-good addresses to send new advertisements to, rather than lists of people to remove. Oh well.

Now, unfortunately I feel compelled to bore you with the saga so far, involving telephone hang-ups, broken privacy policies, and the like. But there is a silver lining at the end, in which I submitted a request to the postal service asking them to block Dell from sending me any more mail, and it appears that they are very likely to violate Federal Law any day now.

I have called them about it. Dealt with the old “let me transfer you to the correct department” then hang up on me ploy. Spoken to people that have promised up and down that I’ll be off their list in 30-60 days. It’s always 30-60 days, isn’t it? Very convenient that I can’t tell for 2 months whether or not they’ve processed my request.

I’ve tried their online chat. One of my attempts went like this:

Session Started with Agent (Sneha Ranga)

Agent (Sneha Ranga): “Due to circumstances that have affected Dell Communications I am temporarily unable to pull up any information. The down time is temporary. We apologize for the inconvenience, as we value your time as a customer. Please contact us back after an hour.”

Session Ended

Ah Dell, only you could reach such a pinnacle of customer service. /kicking someone out of a chat room before they have a chance to say a word.

Finally, last fall, I blogged about the situation (that’s the link above). Debbie from Dell read the post and emailed me. Great, I thought. She asked for my address information and catalog information and sent me a removal confirmation:

From: Debbie@Dell.com
Date: Thu, 18 Oct 2007 13:08:18 -0500
To: jgoerzen@complete.org
Subject: RE: Dell mailing list

Thank you, Mr. Goerzen, your request to have the below address
information removed from our marketing lists has been received:

[ my address here ]

We will process your request promptly. However, it may take several
weeks for some changes to take effect. If you are still receiving
catalogs after thirty (30) days feel free to email me. Sorry for any
inconvenience you may have experienced.

Thank you,
Debbie

So that was October. In December, I replied to that message, saying: “I received another mailing today, and it’s been nearly 2 months since your initial message. If there’s anything further you can do, I’d appreciate it.” Debbie said, “I am very sorry Mr. Goerzen, I will resubmit your request.” Guess how successful that was.

So in February, I manage to figure out a way to send in a support ticket without having a Dell system serial number. I wrote:

I keep getting your Dell Home and Home Office catalog. I have tried for months to get off your mailing list. I have called in, talked to people in multiple departments, who have promised to remove me from the list. I have contacted you online. NOTHING IS HELPING. This has gone on for MONTHS.

PLEASE NEVER SEND ME MAIL AGAIN, EVER, AND DO NOT RENT OR SHARE MY NAME.

My address is above.

The code on the mailing I received is: [ snipped ]

The form letter I got back said:

If you are currently receiving our catalog or mailings and would like to be removed, please visit the following web page and select the appropriate link under the “Opt-out of direct mail, phone or fax communications” heading: http://www.dell.com/OptOut

I replied, saying that form didn’t work. Guess what I got back?

Thank you for signing up for Dell Email Subscriptions. Please save this email for your records.

Yes, that’s right. Asking them to take me off their postal mailing lists got them to PUT ME ON their email lists. ARGH.

So they eventually manage to correctly take me off the email list, and of course promise to do the same with the postal list. This back in February.

I contacted them again in March and July, only to have a similar stupidity-laced run-in with clueless form-answer-laden Dell support reps. Each one claimed to have now, finally, and permanently removed me from the list. It never happened, and none of them lifted a finger to find out way, and no amount of begging could make them.

So, here’s the good part.

Junkbusters has spent years educating people on how to get rid of unwanted mail, and documents getting a prohibitory order against the sender. It was originally designed for people that didn’t want to receive obscene advertising mailings, but thanks to the happy fact that one non-adult-mailer challenged a prohibitory order all the way to the Supreme Court, you can now get prohibitory order against anyone. Yes, even Dell. (The supreme court’s ruling even gave an example: you can prohibit a clothing catalog if you want.)

And last month, that’s exactly what I did. The USPS sent me back a copy of the letter they sent to Dell, as well as a second page with instructions on reporting violations. Here’s the letter they sent to Dell:

dell-usps

Somehow I get a chuckle over some Dell mail clerk trying to figure out how an 11-pound laptop is sexually provocative.

From August 25 on, it is a federal offense for Dell to send me another Home and Home Office catalog. This is a branch of criminal law, not civil law. That is, it’s the maybe-go-to-jail branch of law.

How disappointed I was to receive yet another catalog from them today. If only they had waited 5 more days, I could have turned them in now.

Oh well. There’s always next month’s catalog. Let’s just hope the clerk that received the USPS letter removed my name with a better system than everyone else at Dell uses, eh?

I Want Something eBay Doesn’t Have

Software,

I always have time to think while mowing the lawn. And today while mowing the lawn, I got the notion that it would be great fun to play Colossal Cave and other early text adventure games on a teletype. And, of course, since Linux has teletype support in its genes, if I played my cards right, I could probably get a login prompt to my workstation with the teletype, too.

Now, at this point, I am compelled to take a small diversion and explain just what a teletype is — for those of you, like me, who are too young to remember them. (I will graciously omit comment on those of you too old to remember them!) Teletypes have been around since about the 1930s or so, but the ones I have in mind are the ones that were used to interact with computers in the 1960s and 1970s. Instead of a keyboard and monitor, you’d have a keyboard and printer. Believe it or not, surplus teletypes were the interface of choice for teletypes even in the later years because they were so much cheaper than video terminals.

So anyhow, back to the plot. Teletypes operated at speeds ranging from about 40bps to 110bps, but it seems that the most common protocol was Baudot-coded 50cps 5N2 serial format — that is, 5 data bits, 2 stop bits. Amazingly, the serial UART in modern PCs is still capable of communicating with these devices (though it may take some circuitry to tweak the voltages), and at least one person has made it work with Linux.

So I zip on over to eBay to look for teletypes. What do I find? NOT A ONE! A few manuals, and apparently there is a GPS named the teletype. And some company that has something they think *might* be compatible with a teletype, but they don’t know.

eBay has sorely let me down. An antique geeky item should be right up their alley, and zilch. They can sell everything from cars to advertisements on some guy’s bald head, but not a teletype? C’mon!

So anyhow, I am afraid I will have to improvise. Perhaps I can find a dot-matrix printer with a serial port (or, I guess, a parallel port would do too) and an unbuffered printing mode. Then the trick would be getting keyboard input. Perhaps I could rig up a pty to do this, input from /dev/console, output to /dev/ttyS0. It would still be old, but not quite the real deal.

So if any of you have a working teletype you’d like to get rid of, do please let me know. I’ll send you a photo of the printout of me getting lost in Colossal Cave.

Oh, and for those keeping track at home, I guess you can add this to the list of old technologies I’m interested in: Gopher, typewriters, teletypes… they’re all alike, right?

Asus violating GPL again?

Linux

There was a small firestorm last year when people realized that Asus was not releasing source code to GPL’d components of the EeePC. At the time, they eventually did post source code on their website.

Recently I bought an Eee 901. Asus has modified the kernel’s ACPI driver. They released the source code to that on an 8G surf model, but the 901 has additional hardware features in the ACPI space (bluetooth radio power toggle, for instance) that are not in the source they released back then. There are no sources released at all under the 901 section of their website.

Anyone know whom to contact at Asus about this?

Weird Firefox Problem

Software

Once again, I find myself turning to this wonderful series of tubes for help on a weird problem.

I have Firefox (Iceweasel) on all the computers I regularly use. One of these computers has had a persistent problem.

After using it for awhile, it takes a really long time to look up hostnames in DNS. And after upgrading to Firefox 3, it got much worse. Not only did name resolution get slow, but sometimes page loads would get exceptionally slow as well. I could have 5 tabs open, and all of a sudden at the magic moment, nothing would load on any tab. It was as if I was being hit by 75% packet loss. And new pages wouldn’t load, either.

tcpdump showed Firefox not even sending out packets at these times. After a few minutes, it might be back to normal. But I could always quit and restart and it would be fine.

Now, here’s the weird thing: I’ve eliminated every possible difference I can think of between this one machine and the others I use Firefox on. My plugins and extensions are the same set with the same versions. My configuration is the same. When this problem is happening, other network-related programs (even other web browsers) on the same machine are working fine. Nobody else here seems to be having this problem.

Any ideas?

The Eee 901: Awesome

Uncategorized

An Eee 901 showed up here recently, and I’ve had a (little) time to play with it.

What an awesome little machine that thing is. The keyboard is better than I expected, and so is the screen.

I got annoyed at the lack of things like Emacs on the default Xandros install, so decided to zap it and install Debian. But first, I wanted to take a backup of it.

I was thinking to myself that this is a Linux environment, but I can’t just boot up a Linux rescue thingy to get stuff off it because it’s not a regular PC.

Oh wait. It IS a regular PC. It is so small that I wasn’t even thinking about it in the right terms. So a little dd, gzip, and nc later I have my backup image.

Debian went on smoothly — booted from a 16MB image on a USB drive. X, suspend/resume, etc. all worked out of the box. Compiled the wifi driver and it works.

This is, I think, the perfect laptop size. Also the price is good, it’s solid… what’s not to love?