Showing posts with label terminal. Show all posts
Showing posts with label terminal. Show all posts

Saturday, April 19, 2025

Let's give PRO/VENIX a barely adequate, pre-C89 TCP/IP stack (featuring Slirp-CK)

I had this grand idea many moons ago about writing up a TCP/IP stack for the Commodore 64, along with a lot of other people, and several of those people eventually did so before I even wrote a single opcode of 6502 assembly. For that purpose I had bought the box set of TCP/IP Illustrated (what would now be called the first edition prior to the 2011 update) for a hundred-odd bucks on sale which has now sat on my bookshelf, encased in its original shrinkwrap, for at least twenty years. It would be fun to put up the 4.4BSD data structures poster it came with but that would require opening it.

Fortunately, today we have AI we have many more excellent and comprehensive documents on the subject, and more importantly, we've recently brought back up an oddball platform that doesn't have networking either: our DEC Professional 380 running the System V-based PRO/VENIX V2.0, which you met a couple articles back. The DEC Professionals are a notoriously incompatible member of the PDP-11 family and, short of DECnet (DECNA) support in its unique Professional Operating System, there's officially no other way you can get one on a network — let alone the modern Internet. Are we going to let that stop us?

Of course not! Here's our barebones network stack for PRO/VENIX, the Pro's only official Unix option, downloading the Google home page on real hardware (internal addresses bleeped out) over SLIP and a Crypto Ancienne proxy for TLS 1.3. And, as we'll discuss, if you can get this thing on the network, you can get almost anything on the network! Easily portable and painfully verbose source code is included.

Saturday, January 18, 2025

The "35-cent" Commodore 64 softmodem

Rockwell famously used 6502-based cores in modems for many years, but that doesn't mean other 6502s couldn't be used. If only there were a way to connect a Commodore 64's audio output directly to an RJ-11 plug ...
Of the many interesting posts from Usenet's more golden days, one of my favourites was John Iannetta's "35-cent modem," where the SID chip provides one-way data modulation to a receiving modem connected via the C64's sound output. While I remember him posting it back in 1998, I never actually tried it at the time.

Wouldn't you know it, but it came to mind the other day when I was looking at a recent haul of Convergent WorkSlate stuff I've got to catalogue. Officially the WorkSlate's only means of telecommunications is its 300 baud internal modem. While we have a 9600bps way of wiring up a Workslate to a modern computer, it's always nice to have a simpler alternative, and I figured this would be a great challenge to see if John's old program could let my Commodore SX-64 talk to my WorkSlate. Spoiler alert: it works!

Tuesday, September 3, 2024

Programming the Convergent WorkSlate's spreadsheet microcassette future

In this particular future, we will all use handheld spreadsheets stored on microcassettes, talking to each other via speakerphone, and probably listening to Devo and New Order a lot. (Though that part isn't too different from my actual present.)
It's been awhile since we've had an entry for reasons I'll talk about later, and this entry is a doozy. Since we recently just spent a couple articles on a computer whose manufacturer insisted it was mostly a word processor, it only seems fitting to spend some time with a computer whose very designer insisted it was mostly a spreadsheet.

That's the 1983 Convergent WorkSlate, a one-of-a-kind handheld system from some misty alternate history where VisiCalc ruled the earth. Indeed, even the "software" packages Convergent shipped for it — on microcassette, which could store voice memos and data — were nothing more than cells and formulas in a worksheet. The built-in modem let you exchange data with other Workslates (or even speak over the phone to their users), and it came with a calculator desk accessory and a rudimentary terminal program, but apart from those creature comforts its built-in spreadsheet was the sole centre of your universe. And, unlike IAI and the Canon Cat, I've yet to find any backdoor (secret or otherwise) to enable anything else.

That means anything you want to program has to be somehow encoded in a spreadsheet too. Unfortunately, when it comes to actually programming the device it turns out the worst thing a spreadsheet on an 8-bit CPU can be is Turing-complete (so it's not), and it has several obnoxious bugs to boot. But that doesn't mean we can't make it do more than balance an expense account. Along the way we'll examine the hardware, wire into its peripheral bus, figure out how to exchange data with today's future, create a simple game, draw rudimentary graphics and (with some help) even put it on the Internet with its very own Gopher client — after we tell of the WorkSlate's brief and sorrowful commercial existence, as this blog always must.

Saturday, March 2, 2024

An Apple district manager's Macintosh Portable in 1989-91 (featuring GEIS AppleLink and a look at System 7.0 alpha)

A few months ago I introduced you to one of the more notable Apple pre-production units in my collection, a late prototype Macintosh Portable. But it turns out it's not merely notable for what it is than what it has on it: a beta version of System 6.0.6 (the doomed release that Apple pulled due to bugs), Apple sales databases, two online services — the maligned Mac Prodigy client, along with classic AppleLink as used by Apple staff — and two presentations, one on Apple's current Macintosh line and one on the upcoming System 7. Now that I've got the infamous Conner hard drive it came with safely copied over, it's time to explore its contents some more.
We'll start with this Macintosh Portable itself and Apple's sales channel applications, moving from there to a brief presentation of Apple's Macintosh product line as Apple's own marketing staff would have presented it, at a distinct point in the company's history.
After that, we'll also look at the upcoming System 7.0 circa 1989-90 and a couple very different views of the operating system during its alpha phase.
Finally, after a brief glance at Mac Prodigy, we'll explore a little taste of AppleLink in its classic incarnation on General Electric's Mark III network — and spoof it enough to actually get it to log in.

Thursday, January 18, 2024

Reversing the Web-@nywhere Watch: browse fragments of the Web on your wrist

In the halcyon days of analogue modems and POTS dialup Internet, when the only wireless connection in your house was between the cordless phone and the wall, anything having to do with the Web was best consumed in small bites (pun intended). If you wanted to take data with you, you downloaded it first.

Which brings us to this.

Smartwatches at the turn of the century were a more motley assortment than today's, with an even wilder range of functionality. If you had a few hundred dollars or so, there were some interesting options, even back then. But if all you had was $85 (in 2024 dollars about $150), you still weren't left out, because in 2001 you could get the Web-@nywhere (the "Worldwide Web Watch"). Load up the software on your PC and slap it in its little docking station, and you could slurp down about 93K of precious Web data to scroll on the 59x16 screen — 10 characters by 2 characters — to read any time you wanted!

That is, of course, if the remote host the watch's Windows 9x-based client accessed were still up, on which it depended for virtually anything to download and install. Well, I want 95,488 bytes of old smartwatch tiny screen Web on my wrist, darn it. We're going to reverse-engineer this sucker and write our own system using real live modern Web data. So there!

Saturday, October 28, 2023

What the KIM-1 really needs is an LCD screen

Giving the 1976 1K RAM, 1MHz 6502-based KIM-1 single-board computer bubble memory storage was all well and good, but the basic unit is still just six numeric LEDs for its display. Let's solve that problem.
Here's a sidecar screen for my KIM-1 that's large enough to be useful, small enough to be portable, and efficient enough to be powered by my unit's built-in power supply. Plus, it can be driven by the KIM-1's unallocated I/O lines so that its 20mA current loop terminal interface remains available, with bonus points for being self-lit so you can see it like the LEDs. And the output driver takes up just 64 bytes of RAM.

Monday, September 11, 2023

The spawn of AtariLab and the Universal Lab Interface

We were a Commodore 64/128 household growing up, and Apple IIe systems at school, but that doesn't mean I was unaware of Atari 8-bits. There was a family at church who had an 800XL and later a 130XE — and a stack of COMPUTE!'s I used to read through for hours — and it was interesting to compare the two worlds, especially the relatively luxurious Atari BASIC and DOS against Commodore's spartan accoutrements. On the other hand, there was a lot more software and peripherals for the C64 by then, and you ended up becoming a lot more proficient with the guts of the hardware because you had to. Plus, Jack Tramiel's Atari was a lot like Jack Tramiel's Commodore and not always in a good way. I have an XEGS (functionally a 65XE when you add the keyboard) and a 1050 disk drive I should set up somewhere and mess around with a little.

But that doesn't mean Atari didn't try. Prior to all that, Atari in the Warner Communications days put forth substantial effort to make it competitive in all kinds of settings, notably education. Ataris had some unique hardware in that niche; an Atari was the first non-Control Data microcomputer to access the PLATO network, for example. And then there was the AtariLab.

With a very simple interface box, your Atari 8-bit could read the temperature and sense brightness. You could run experiments on it at school, including polarized and coloured light, or testing how quickly things cool and heat. You could use it at home with your own programs thanks to its comprehensive documentation.

But the surprising part is that even though these were the only such devices released under the AtariLab name, they weren't the end of the line: besides its stealthy revival for other home computers like the Commodore 128 running it here, its creator also turns up in one of the more interesting scientific data acquisition devices I've run across in its price range. We'll test-drive the software, hack on the platforms a little, and try some even more outlandish sensors. Let's go down the rabbit hole with AtariLab — and its full-fledged descendants.

Friday, May 19, 2023

The KIM-1 that sounds like Stephen Hawking (or: "jitbanging" DECtalk)

My 1976 briefcase Commodore/MOS KIM-1, a 1 MHz single-board computer with a 6502 CPU and 1K of RAM, has learned to talk — with a familiar-sounding voice.

The KIM-1's serial lines are connected to the last and smallest member of Digital Equipment Corporation's true DECtalk hardware speech synthesizers, the 1994 DECtalk Express. The DECtalk's classic default voice heard in this video is Perfect Paul, which (with adjustments) was the voice of Dr Stephen Hawking as produced with the 1988 Speech Plus CallText 5010.

The 15 keys we can read off the KIM's hexadecimal keypad are polled by a "talker" program that sends the DECtalk Express words and phrases to speak. However, although the KIM-1 has 20mA current loop output you can turn into RS-232 serial, its built-in ROM routines can't reliably communicate at the 9600 baud rate the DECtalk Express demands.

So, in today's entry, we have a veritable smorgasboard of geriatric geekery: using our KIM-1 serial uploader to push a program for execution, let's write a bitbanged 9600 baud serial transmitter routine in 6502 assembly and let the KIM-1 have its say — and crack the DECtalk Express open and look at the insides while we're at it. (Teaser: you'll find its CPU very familiar.)

Tuesday, March 21, 2023

Printing real headline news on the Commodore 64 with The Newsroom's Wire Service

Besides other things I've written or supervised, so far in my time I've also edited three periodicals, and Springboard Software's The Newsroom is a big reason why. In today's article we'll not only look at the guts of this pioneering 1984 software package, but also solve a childhood mystery I've wondered about since the very first day I touched the program by MITMing an RS-232 connection to snoop on serial data — and then print out a brand new 2023 newspaper with 2023 headlines to prove we cracked the case. (Scroll to the end if you just want to see the finished product.)

Sunday, September 4, 2022

What the KIM-1 really needs is bubble memory (plus: 20mA current loop for fun and profit)

It seems like everything has flash. Flash mobs, flash photography, Flash Gordon, flash memory. (Other than the past couple years, of course, which haven't been very flash.) And, because solid-state-all-the-things, you can get flash storage devices for tons of classic computers where even the tiny microcontroller in the SD cards is probably more powerful than the systems they're being interfaced to. Why, you can even connect one to an MOS KIM-1, the famous mid-1970s MOS 6502 single-board computer. Now at last you don't need to rekey everything in or screw around with an audio recorder.

But, of course, if you've read this blog for any period of time you know I don't go in for that sort of new-fangled nonsense around here. I like my retrocomputing frivolities period-correct. What the KIM-1 really needs as a mass storage medium ... is bubble memory.

Sunday, April 10, 2022

Tonight we're gonna log on like it's 1979 (Telenet, Dialcom and The Source)

Teletypes may have killed a lot of forests by emitting every line to hard copy instead of a screen, but there's something to be said for the permanence of paper, especially when people hang onto it for some reason. While getting duff units to build a functional Silent 700 Model 765 ASR teletype, which will of course be a future article, one of them was more interesting for what else it came with: a set of teletype transcripts of several users logging onto The Source, one of the earliest online services, and a complete photocopy of the service's user manual. So get out your copy of Pink Floyd's The Wall, start blasting "In The Flesh," and let's head back to 1979 and 1980 when these transcripts were printed. We'll talk a little bit about the service generally and then log on exactly as these people did — because the Silent 700 transcripts indeed show exactly what transpired and how they used them.

Thursday, February 17, 2022

Refurb weekend: Texas Instruments Silent 700 Model 745 teletype

The first terminal I ever used was a teletype. Somehow my buddy when we were in high school got a hold of this weird "printer typewriter" which was none other than one of the famous Texas Instruments Silent 700 series.