Hot off the heels of their musical debut 6502 song the good folk at the Taylor and Amy Show are at it again. This time instead of assaulting our auditory senses, they play with our perception of color all while keeping the spirit of retro computing alive.

To back up a bit, I had the pleasure of witnessing the discovery of the Avon Beauty Vision Computer while at the Vintage Computer Festival Mid-West (VCFMW) this past September. We had visited the home of our friend [Jim W] from VCFMW who nonchalantly pulled down from the shelf the reddest computer I have ever seen.

A crowd quickly gathered at this newfound treat, designed and built before the invention of the Blue LED, was fallen upon and the process of prying out its secrets began. I was not privy to the negotiations, but I did notice a brightly colored red suitcase being exfiltrated by highly trained operatives later that night.

The next day several of the outdoor tables at said VCF Midwest event were relegated to the effort to breathe life into the aging T1000 Cyberdyne Toshiba system that ultimately powered the Avon Beauty Vision Computer (ABVC). The ABVC was created to provide personalized makeup suggestions to users based on their skin tone as measured by some sort of large optical gun. “Combining facial analysis with Avon’s beauty database, it offered tailored recommendations” …in theory. More about the Avon computer can be seen in LGR’s video.

It was a long day of repair ups and downs; success, followed by failure, followed by success, with almost no mistakes made. People stopped by to offer opinions and prayer throughout the day until finally [Taylor] proclaimed “It’s ALIVE”. She was wrong but it was still an impressive moment. Later it really did work, but we weren’t falling for that again.

As seen on their video [Taylor and Amy] found the existing software and its results to be… wanting. A bright Disco Green was in their future as recommendations for both women consisted of a subtle palette of mostly refined taste… for the 1980s. 

Cleary the outdated software needed to be updated. A Brownian Motion Generator was consulted and it was decided that the color palettes should be Gothified. Look it up, it means “to make Gothy”.

What’s amazing is the effort that went into Gothifying the firmware, as I am told that [Jeri Ellsworth and Amy] from @TiltFive, but mostly [Amy], stayed up late editing raw hex code so that the printout was real. This was a great touch as I would imagine they had to come up with words that fit the sizes of the existing words such as “Violent Violet”. As a hardware engineer I would have just preprinted the paper rather than do the actual work, but not this crowd.

What was needed was field testing which resulted in the Goth Makeup Palette Challenge where some of us would submit to the mostly painless process of having our palates determined. I was in the blast zone when the challenge was decreed and gladly accepted the opportunity to dawn long locks of hair in a futile attempt to recapture my Bad Boy period of the 1980s. 

The blast zone of those affected included old friends such as [Ken] from @CanadianRetroThings, [Robin] from @8_Bit, and [Evie] from @EviesRevue, as well as new friends [Veronica] from @VeronicaExplains who also shows us her trip to the VCF MW. I had looked forward to meeting [AJ] and [Tim] from @mydrunksibling but apparently and unfortunately, [Tim] did not survive the filming of the insert.

As you might be able to tell, attending a Vintage Computer Festival is not just about cool electronics, but also about the people that you meet and the friends that you make.

In a wonderful ode to tech nostalgia, The Taylor and Amy Show, comprised of YouTubers [Taylor] and [Amy], have released a new video “THE 6502 SONG”. This song had me singing along in roughly six clock cycles, possibly a little dancing around may have occurred as well. This isn’t just any chip they’re singing about; it’s the venerable 6502 microprocessor, the silicon heart behind iconic machines like the Apple II, Commodore 64/128, and the Atari 2600.

Their lyrics reminds me of when I lived for assembly language mnemonics and counting clock cycles, the “feeling” of a processor coming out of tristate to pronounce what it had learned in the last 500ns, and the undulations of the DRAMs like speed bumps. To top it off, portions of the song were actually recorded live at the Vintage Computer Festival Midwest 2023, where fans and computing history aficionados alike were treated to an impressive display of vintage tech.

What sets “THE 6502 SONG” apart isn’t just its catchy, melodic tune; it’s the expert blend of historical detail and genuine enthusiasm that resonates with everyone from grizzled assembly-language programmers to youngsters newly fascinated by the allure of 8-bit computing. With guest appearances from other female tech YouTubers like [Veronica Explains] and [Evie’s Revue], [AJ], [Jeri and Amy- Tilt5] and [FuzzyBad].

I believe [Chuck Peddle] father of the 6502, would be proud to see his creation live on and be appreciated so.

Our friend [Fran Blanche] recently recorded what it was like to participate in an energetic round table at the recently held Vintage Computer Festival (VCF) East. Fran joined well known personalities [Jeri Ellsworth], [Adrian Black] of Adrian’s Digital Basement, and Usagi Electric creator [Dave Lovett] with yours truly moderating.

The table-less roundtable discussed the pros and cons of streaming about retro and tech, and what its like to hang yourself out there in video format. Goals and motives differed widely from speaker to speaker and there was some good-natured ribbing about who makes money vs. who simply gets away with spending less.

Most of all fun was had by the speakers as they interacted with each other, and with the audience — and that comfort came across to the standing room only crowd of avid retro-enthusiasts who only told us good things about what they saw and heard that night.

One thing we did note was that every speaker actually knew what microphones were and how to use them.

Want to learn more about the 2023 Vintage Computer Festival East? You can start by checking out our previous coverage, and don’t miss the first in a series of fascinating interviews recorded by the Hackaday crew as they explored this phenomenal retrocomputing event.

A new Commodore C128 cartridge in 2023?  That’s what [idun-projects] set out to do and, as you can see in the video below, did. I did the original C128 hardware design and worked with the amazing team that turned this home computer out in 1985. Honestly, I am amazed that any of them are still working 38 years later, let alone that someone is making new cartridges for it.

I also never thought I would hear about someone’s in-depth experience designing for the ‘128. The post takes us through [idun-project’s] decision to use the ‘128 and how modern expectations apply to all computers, even the old ones. Hot on the list was connectivity and reasonable storage (looking at you, floppy disks).

With newer expectations comes newer tools and, yes, operating systems.  The project draws inspiration from the ACE “Advanced Computer Environment” created by [Craig Bruce] in the 1990s, a mere 20 years ago.

Tackling 6502 assembler programming in the new environment, [idun-project] set about the goal of making the C128 talk to a Raspberry Pi without burdening the Pi down too much, hence a cartridge based on the Parallax Propeller 1. Even overclocked, though, it was a challenge to match the 6502 bus.

Frankly, when I hear about a piece of C128 hardware surfacing, I expect it to look more like the one [Drygol] restored. Of course, if you have the Propeller, you could just emulate the whole computer.

This year marks the anniversary of the most popular selling home computer ever, the Commodore 64, which made its debut in 1982. Note that I am saying “home computer” and not personal computer (PC) because back then the term PC was not yet in use for home computer users.

Some of you have probably not heard of Commodore, which is kind of sad, though there is a simple reason why — Commodore is no longer around to maintain its legacy. If one were to watch a documentary about the 1980s they may see a picture of an Apple computer or its founders but most likely would not see a picture of a Commodore computer in spite of selling tens of millions of units.

To understand the success of the C64 I would first back up and talk about the fabled era of home computers which starts with understanding the microprocessor of the day, the venerable 6502. Check out the video and follow along below.

The 6502

The 6502 was the brainchild of Chuck Peddle and a team of engineers, Bill Mensch, Wil Mathes and others, who were all working at Motorola — we called them the Motorla Five even though there were seven of them.  Chuck’s team successfully shrunk down a full sized PCB known as the main processor board onto a single chip, known now as a microprocessor, the 6800 to be exact.  While this evolutionary step seems whole and natural to someone like you or I, the existence of the microprocessor was deemed a threat to those at Motorola who made their money selling the main processor board for tens of thousands dollars vs the $250 that the 6800 was slated to sell for.  Mr. Peddle basically received a “cease and desist” letter from Motorola to stop work on the 6800 which Chuck took to mean that they were abandoning the project and the intellectual property it represented.  Chuck and company then joined MOS Technology in Norristown PA and subsequently released the 6502 microprocessor which sold initially for $25 and ultimately less than a dollar. The fact that the lawyers disagreed with Chuck is a different story.

KIM-1

The 6502 is at the heart of many of the home computers of the era starting with Atari, Apple, BBC Micro, and of course Commodore.  One of the earliest examples of the 6502 was a system known as KIM-1.  Contrary to popular belief, the KIM-1 was not designed by Chuck Peddle but rather someone from the Calculator Group at MOS lead by John May. When asked about his contribution to computers in general, Mr. Peddle’s response was that he was proud of the Input/Output (I/O) chips of the day as a computer with no I/O is just a processor but add I/O and you have terminals, cash registers, printers, etc.

I cut my teeth on the 6502 as a young bench technician at a company named Pennsylvania Scale Company in the late 70’s, doing processor controlled instrumentation which was pretty much a burgeoning field at the time. Turns out I had an affinity for how microprocessors “thought” and had worked my way up to the title of Hardware Design Engineer by the time I applied for a job at Commodore, fair to say that I would not have had my career in electronics without the existence of the 6502.

Sometime during this time Commodore, under the reins of its founder Jack Tramiel, purchased MOS technologies and became a computer company that owned a chip fabrication plant known as a chip fab for short. Though the purchase of the chip fab was initially instituted with an eye on the calculator market, Commodore found itself in the position of being a computer company that could make its own (custom) IC’s, or chips. This would change how home computers were designed in the days to come.

PET

Chuck’s next endeavor centered around the line of computers known collectively as PET. Chuck had told me what PET stood for in his mind, but I have since forgotten which of the several interpretations is correct. PET computers had a built in keyboard and monitor which was important back then as usable monitors were somewhat rare.  The PET found a home in business, academia and industrial usage and so was something of a predecessor to the “home computer” in my book.

The VIC Chip

Meanwhile a chip designer known mostly for designing Read Only Memory (ROM) named Albert Charpentier made it his goal to design a new video interface chip, the chip that made computers exciting due to the colors and motion that could be created.  To prove the chip  was doable in a very 1970’s fashion, Albert designed a PCB to prototype the new video controller IC, a chip that was to become known as the VIC-1 chip.  This chip was designed specifically to integrate with the 6502 processor and was tightly integrated with the address/data busses and control signals The story goes that it was 11:00 at night when suddenly the color display started working and the VIC chip’s legacy started.

VIC-20

At one point a system was built around the VIC chip in order to show off the chip’s capabilities, a system designed by Charpentier and a young chip designer named  Bob Yannes who went on to design the popular SID chip — more on that later. Talk then turned to selling that system as a new computer product.  A relatively young programmer named Bob Russell is credited with convincing the boss, Jack Tramiel, that if Commodore was going to sell a computer based on the VIC chip that it should be a “real” computer and the project was transferred to Chuck Peddle’s group who had the experience of designing and producing the PET.  Ultimately this computer became known as the VIC-20 and was designed by an engineer named Bill Seiler, with the software code being written by John Feagans and  Bob Russell.

The VIC-20 was Commodore’s “TI Killer” as it targeted the same space that the Texas Instruments TI-99 computer system was selling into. The VIC-20 had 4 – 5 kB of Random Access memory, 16 kB of ROM and built in sound in the form of three sound generators in the VIC chip.

It was during this time that Commodore started to exercise its overseas manufacturing capabilities which would later set it apart from other home computer companies.

Next, Albert Charpentier set his sights on a new version of the VIC chip, this time with the inclusion of Movable Object Blocks known in the industry as “sprites”.  These are predefined blocks of graphics that can be moved around by simply changing pointers as opposed to continuously using the processor to move the object around the screen.  The sprites were also capable of letting the processor know when they collided with each other, an important aspect when gaming,  freeing up the processor even more.

Behind the scenes, Albert had taught the VIC chip to share the main memory bus with the 6502 processor in a way so as to make use of an unused window in time to get most of the graphics done: it “shared” the memory bus in a multiplexed fashion.  The decision to do multiplexing  was brilliant in my humble opinion, and would go on to be a feature of most all of the Commodore computers to follow to include the Amiga line of computers.

SID and the C64

The SID chip included features such as envelope generators, oscillators, and filters, all components of the musical synthesizers of the day.

Much like the VIC-20 before it, these amazing chips were combined into a demo and shown to Jack Tramiel, and the decision was made to produce the Commodore C64. The C64 is listed in the Guinness Book or World Records as the most popular home computer ever sold at 27 million units.  In the time since, there has been some analysis of serial numbers that suggest that fewer units were sold in actuality, but there is little doubt that it far outsold the competition.

The C64 became Commodore’s “Apple Killer” as it was targeted at the market shared with the Apple II.  The price of the C64 started out at $595 USD, lowered to $299 and finally lowered to $199 at a time when the competition cost over $1,000 .  During this time, Commodore’s founder Jack Tramiel stated famously that we made “computers for the masses not the classes” with emphasis on selling the hardware at a fair price which would open the door to massive software sales.

The C116

The C116 was my first introduction to the inner workings of Commodore as a young, enthusiastic design engineer employed by MOS Technologies/Commodore Business Machines.  My boss Shiraz Shivji showed me the color Spectrum computer made by Timex Sinclair and said that this was what we were going after.

C264/C364V

Next in the family was the C264 computer, a 64 kB Byte computer with the same 121 colors and simple sound.  The computer was nowhere near as interactive as the C64, as it lacked sprites and the dedicated SID sound chip, but our attitude was that someone who wanted a game machine should “buy a C64”. This was meant to be a  dedicated text and static color machine for business. We developed new printers, disk drive, and monitor to round out the family. The C264 was designed to sell for $79 USD.

The last of the TED series was the C364V, where “V” stood for voice.  Commodore had acquired some of the talent that made the groundbreaking TI Speak-and-Spell.  With this leg up on the voice interactive market Commodore was set to release the “Talking Magic Desk” a desktop motif that gave verbal prompts which was very aggressive for 1984.

We showed the entire suite of “TED” computers and peripherals at the 1984 CES show.  Before leaving the show we started hearing rumors that Commodore’s founder, Jack Tramiel, had quit, which we sadly found out to be true.

One positive aspect of the TED project was that Commodore finally built a $79 version of the computer known as the C16. We still hear from people who grew up in Europe that their first computer was a C16.

The hardware for the TED was done by myself and Dave Haynie — the design was already done when I got there — and the software was done by Fred Bowen, Terry Ryan and John Cooper as shown in the TED Easter Egg.

The Commodore LCD

As the engineering was ramping down for the TED series, we started to work seriously on our next computer, the Commodore LCD.  Commodore had not been idle and had purchased a manufacturer of LCD assemblies named Eagle Pitcher, and became the only US based company that could produce.  We did the initial architecture of the LCD based upon a central Memory Management Unit (MMU) as we were trying to speed up the 6502 of the day through some memory management tricks. Ultimately we turned the hardware effort over to Jeff Porter and Ian Kirschman with software being done by Hedley Davis, Andy Finkle, and Caryolyn Scheppner. The LCD system was slated to be the next evolutionary step in the Commodore product line, but sadly it was canceled by the person that replaced Jack Tramiel.

Finally, we heard that the end of the 8-bit era was upon us in the form of the 16/32 bit Amiga computer, a recent acquisition by Commodore of what was basically a bunch of ex-Atari engineers designing the next generation coin op video game that Commodore was set on turning into a business machine. There was just one problem, the Amiga wasn’t slated to be completed for at least another year.

C128

A bunch of engineers got together and decided that we could squeak a final 8 bit computer through in the time available before the Amiga would fully hit.  All of us knew from experience that a computer that would require all new software was a non-starter, at least not without commitment from upper management which seemed to be missing now that Tramiel was gone.

Including a C64 compatibility mode just made sense to us engineers as did the name C128 to reflect having twice the memory of the C64. (The C128 was designed to support a total of 512 kB memory but that’s a different story.) The design was mostly completed and a working example running a C64 game was shown to management which struck a chord with said management who were pining for the days of huge sales of the popular C64.

The entire story of the C128 development can be found in the book Back into the Storm: A Design Engineer’s Story of Commodore Computers in the 1980s but before it was done, we would have two microprocessors, with the addition of a Z80, as well as three operating systems and simultaneous 40 column and 80 column outputs. It was designed to sell for $199 USD but probably sold more often at $299.  The hardware was done by Bil Herd, Dave Haynie, and Frank Palaia, the software was done by Fred Bowen, Terry Ryan and Von Ertwine.

Vintage Computer Festival

If you can’t get enough 8-bit computing, will be celebrating the anniversary of the C64 this year with the first installment at the Vintage Computer Festival this weekend in Wall New Jersey.  Albert Charpentier will be there as well as Dave Haynie, Bob Russell, Andy Finkle, Hedley Davis, myself, and others.

You can do your own Surface Mount Technology based PCB assembly with just a handful of tools and some patience. At the heart of my SMT process is stopping to inspect the various steps all while trying to maintain a bit of cleanliness in the process.

Surface mount or Surface Mount Technology (SMT) is the modern way to assemble Printed Circuit Boards (PCB) and is what is commonly seen when opening a modern piece of tech. It’s much smaller than the older Through-Hole (TH) technology where the component leads were inserted into holes in PCB, and act we called “stuffing” since we had to stuff the components into the holes.

A few specialized tools make this a lot easier, but resourceful hackers will be able to pull together a solder paste stencil jig, vacuum tweezers, and a modified toaster oven with a controller that can follow the reflow profile of the solder paste. Where you shouldn’t skimp is on the quality, age, and storage of the solder paste itself.

Join me after the break for my video overview of the process I use in my workshop, along with details of every step of my SMT assembly process.

Component Size Matters

Surface mount package names can be a little bit confusing. In the video I talk about pats that have a pin pitch of 0.5 millimeters, but when it comes to resistors, we use numbers like 0603 and 0402 which measure 0.06×0.03 inches. It’s always to good idea to have examples you can reference to ensure you’re using the right size package.

Looking at my trusty Adafruit ruler with component sizes shown I will say that I commonly do the 0603 size components on a regular basis, though I have done 0402 for RF components where less size means less things like inductance which fight you as you go up in frequency. I don’t work with the smaller 0201 components as I am afraid of inhaling them they are so small.

Pretty much all of the SOIC parts you see can be done using the methods I show in the video and I commonly go down to 0.5 mm lead spacing, though in the video I solder some chips which have 0.4 mm lead spacing, the smallest I do in my home lab.

Caring for Solder Paste

Nowadays we “place” a component on PCB’s without the need of holes for the components leads, and instead of applying solder after the fact in its molten form, we use a solder paste consisting of flux and solder. The paste can be packaged in a variety of ways but I buy my paste in syringes and I keep them in a small refrigerator and only for a limited amount of time as solder paste has a shelf life depending on the kind and where you buy it.

Solder paste is denoted by the flux that it is based on, I use “no clean” which means pretty much what it says, the end result is operable without cleaning the PCB. If I am delivering the board to someone else I typically clean it anyways which I go over in the video.

The solder is an amalgam of little beads of solder held in suspension with flux and can be the touchiest thing about DIY soldering as the solder has a definite shelf life of weeks if not days depending on the manufacturer. Simply put if you don’t remember when you purchased your solder, throw it away. I buy a solder formulated for better shelf life named Zeph paste which keeps longer than a production mix, and I store it in a small dedicated refrigerator (think six-pack cooler) and stored upright in syringes with the needle pointed down.

Solder also comes in many types, starting with leaded vs non-leaded and then variations depending on what kind of flux it contains. I use the “no clean” version which doesn’t have to be cleaned, or can be cleaned with alcohol instead of the stronger flux cleaners.

Applying the Solder

There are several ways to get the solder paste on the PCB; it can be manually applied using a syringe and good old fashion squeezing to deposit the solder onto the connector pads of the PCB. I also have an air pressure operated dispenser that I don’t really use.

My go-to method is to use a paste mask stencil and squeegee the paste onto the PCB as seen in the video. There is a trick to squeegeeing the paste to not press too hard while forcing the paste through the paste mask screen. Paste mask stencils are available for a few dollars from the same sources I buy my PCB’s at, for larger runs I would look at companies like OSH Stencil.

Inspect Your Paste, then Place Components

I always inspect the PCB before placing the components on the board and I use a stereo X10 microscope for this step. What I am looking for is anything that would create a solder short later, I.E. if its shorted now it will most likely be shorted later.

The trick is to place components on the board, kind of snuggled into the solder paste really, without smearing the paste or bending the component leads. Tweezers work for smaller components like resistors and capacitors but often for Integrated Circuits (ICs) one must be careful to lay the package flat. I have a variety of ways to do this using suction including the little suction cup with a squeeze bulb for a fully manual method or when doing a lot I might be inspired to fire up my little suction powered parts picker-upper made out of an old aquarium pump.

At Last, the Oven

I have tried a variety of reflow ovens including the T-962 (complete with mods per the Hackaday articles on the subject) but always found it wanting, especially with tall, dark components as the radiation patter inside the oven is somewhat uneven.

In order to make a better small scale oven I started with a Black & Decker convection oven and bought the Controleo3 oven controller which comes with an auxiliary heating element to boost performance. After applying lots of reflective tape and high temp RTV the oven is sealed against as much heat loss as feasible. The oven controller takes an hour for it to learn the oven’s characteristics but once learned I got really good and repeatable results.

An important consideration is the Solder Profile which is a chart of heat vs. time. It is pretty much the opposite of just sticking the boards in a hot oven until the solder melts, which is pretty much guaranteed to just bake off the flux leaving little clumps of solder as opposed to the smooth reflow that we want to achieve. The Solder Profile takes care of various phases such as preheat and rapid cooling in addition to the actual reflow stage.

I installed an additional heating element on my oven. The Controleo3 calibrates itself to the oven and even the size of what the oven is loaded with. I re-train the oven if doing large PCB’s using a blank board.

Final Inspection

True to my nature I slap the final soldered item under the microscope one last time and look carefully at each lead noting any solder bridges or voids in the process. I am also looking for the solder to have melted thoroughly and not look “grapey” or where the solder may have coalesced into tiny clumps instead of a properly whetted solder joint.

I like to give the boards a trip through my ultrasonic cleaner that I keep just for PCBs. While not usually necessary it gives the boards a nice professional look and makes inspection easier.

Conclusion

Hopefully one can see that doing DIY SMT assembly is certainly possible and can even be done for small scale production. In my case I can solder components down to 0.4mm lead pitch which is pretty small as long as I do ample inspection. Keep it clean, keep your solder paste fresh, and inspect at every step and you’ll get great results in your own workshop.

I miss my friend Dave DiOrio. He was a chip designer in the 1980’s, which made him one of the true wizards back then. We met my first day when I started at Commodore Business Machines, though my paycheck said MOS Technology on it.

MOS Technology was the birthplace of the venerable 6502 microprocessor, the VIC video chip, and the SID sound chip to name the really famous ones. It also brought us the TED Text Display chip, a whole boatload of Amiga chips, and several other chips that almost did what we wanted them to do.

I worked with magicians whose stock and trade were comprised of half-part quantum tunneling effect and half-part straight-up logic implementation. These magicians weren’t bound by the number of pins available for TTL logic, not like us lowly hardware engineers who had to string 14 and 16 pin chips together to do any real lifting.

Below the spartan offices where the designs were drawn lived the dragon otherwise known as a chip fab, short for integrated circuit fabrication plant. This beast ate sand and made wafers; slices of almost pure silicon in crystalline form with all kinds of intricate things craftily grown on top of them.

Memory Lane: Touring the Abandoned MOS Headquarters

MOS Technology was started in 1969 by Allen Bradley but only became the MOS that I think of when I talk about the good old days when Chuck Peddle and a bunch of cohorts from Motorola, including Bill Mensch, swept in and produced the 6502 microprocessor, which resembled a particular Motorola processor quite a bit, in fact a lot. Lawsuits followed.

Meanwhile the 6502 was taking over several industries as the go-to processor for everything from medical equipment to microwave ovens to home computers. It was while designing home computers that I met Dave while standing above a chip fab. I can still remember the smell of that dragon farting below our feet… its an understatement to say I miss those times.

A couple of years ago I had a chance to return to the old stomping ground as it were, and set foot (legally) inside of MOS headquarters in Norristown, PA — which had become CSG (Commodore Semiconductor Group) by the end. The basement was dirty and flooded and yet we found wafers, one from one of the computers I worked on.

The ground floor was dark and quiet, I stood at the dirty glass entrance doors looking out at a drab street and I quickly moved on before I got hit by some sort of self evident metaphor for life that would have been annoying.

The second floor was where our offices had been. The hot press of design deadlines has long since left this space, now all there is to see is the golf course out the window and a little camp fire someone had made. I got to show this video to Dave, including the view looking out his old office window, and we both smiled at the thought that it was now 35 years later.

Dave has since passed away, the world has one less wizard and as the video shows, the dragon has long since gone quiet.