SUPERPROTOs will be at K’Fest

July 12th, 2012

I sent 10 kits to the show – they will be priced at $60 each. One additional kit has been donated to the organizers as a prize/giveaway.

Here is what the built up superproto looks like.

SUPERPROTO

SUPERPROTO

More information is available on the SUPERPROTO wiki. This is currently a work in progress, as there are several areas that need more documentation. In particular is a description of how the copper layer in the proto areas is set up. It is kind of hard to see, since the solder mask tends to conceal the connections between the pads.

I also need to add a page to show how to connect the SUPERPROTO to a separate breadboard for easy prototyping.

More kits will be available in a few weeks, once I catch up on things.

After the grounding issue with the Brain Board, I did as much research on grounding Apple II plug in cards, as I could. This included rereading some Apple Tech Notes on the topic, which were somewhat insightful, as well as examining existing designs.

I really tried extra hard to make the ground plane on this board as good as I could make it, and still keep the 2 layer layout. The result exceeds my expectations, as the ground noise on the base SUPERPROTO card is almost non-existent. The 5 volt supply also received some attention, and it looks clean as well. In fact, the board looks much cleaner than my wire wrapped prototype, so I must have done something right.

Mimeo update

July 3rd, 2012

If you are on my waiting list for Mimeo kits, I should be contacting you in the next few days about PCBs. If you have been waiting for more than a month or two, feel free to remind me about your interest. PCBs will go first to those that have been on the waiting list the longest. The folks at Unicorn Electronics believe that they will have parts kits available as soon as next week. If you are waiting for assembled systems you will have to wait a while longer. I’m planning on doing enclosures this time and everything will take considerable time and effort to put together. I’m up to my ears in ongoing stuff, right now.

New pricing and basic ordering information is posted on my Mimeo page:

http://www.willegal.net/appleii/apple1-kit.htm

Reminder – I will be supplying only PCBs (motherboard and monitor PROMs) – other parts for a complete motherboard kit should be obtained from Unicorn Electronics.

For the smaller kits, like the Brain Board, ACI and PS/2 adapter, I’m still supplying the entire kit.

Great Mimeo Kit News – Kits available soon

June 20th, 2012

PCBS

The batch of boards I purchased last month were all sold as bare boards, so I’m getting a new batch made up. More than half of those boards went to a company in Los Angeles which turned them into non-functional props for the new Steve Jobs movie starring Aston Kutcher. I’m expecting that that movie will feature some cool looking props, when it comes out.

Anyway the new batch of PCBs will take a couple of weeks to arrive.

Kits

I’m excited to announce that there will be some changes for those of you that wish to purchase Mimeo kits. I’ll be selling boards to you and parts kits will be purchased directly from Unicorn Electronics. I’ve sent BOM information to Rob at Unicorn, who is working hard to get all the required parts. Rob tells me that he has most parts on hand, already, but there are a few more to gather. I am really excited about this arrangement, as it should greatly increase the availability of Mimeo’s to the vintage computer hobbyist and free up time for me to work on new projects – a win for everyone. People wanting to build kits would have to take a couple of extra steps to get their kits. I think that this is a small price to pay for increased availability.

Mimeo Assembly Manuals
For hard copy assembly manuals, I’ll probably make it a separate, extra cost option, though I’m also considering using a print on demand service, so you would have to order the manual separately.

Assembled Mimeos
For those of you who want a built up Mimeo, I’m looking into building a few complete systems, with keyboard, enclosure and cassette player. Be forewarned, this sort of system will take a lot of time and money to put together. I haven’t set a price, but the number I have in mind will put it into the luxury item category.

Apple II rev 0 PCBS?
Ordering and putting together kits for Mimeo has been a huge time sink, and this change will allow me more time to work on new projects. If it works out well, I’ll also seriously consider making a new run of Apple II rev 0, reproduction motherboards. Unicorn would become the default parts supplier for that kit, as well.

Simpler Kits
For simpler kits, like the ACI, PS/2 adapter and Brainboard, I will continue to supply the complete kit, just like before.

Vince Briel evaluating doing a cassette interface card

June 19th, 2012

Check out the post on his forum. I think all replica 1 owners should get a cassette interface for their units. Using an ACI is pretty essential to a faithful Apple 1 experience. Back in the the old days, it was…

  • the only Apple 1 expansion card ever offered by Apple.
  • the only way to share software between Apple 1 owners
  • Owners of original Apple 1’s or clones like my Mimeo or the Obtronix understand that without a Cassette interface, an Apple 1 Computer is nearly useless.

    Cassette interface technology can be challenging. Note that Vince’s unit is most likely to incorporate several design features that I first documented either on my web site, or on Applefritter.

  • input coupling cap change to .1UF- see my ACI page
  • referencing voltage comparator to ground instead of -12 volts: see the applefritter post
  • If you can’t wait for Vince to make an ACI board, I have authentic reproducion ACI kits in stock and ready to ship for $75. Drop me an email at mike@willegal.net

    8008 Performance

    June 18th, 2012

    To evaluate real world 8008 performance, I have done some performance measurements using SCELBAL in my 8008 emulator. The 8008 running a typical BASIC program, such as “99 bottles of beer on the wall”, executes around 32,000 instructions per second. That is .032 MIPS, for those of you that measure processor performance that way. In contrast, the 6502 is said to execute roughly 300,000 instructions per second. However that is not the whole story, as instruction set influcences performance of real world programs in a significant way. For example, a single memory access on the 8008 will require 3 instructions if the H and L registers are not set up in advance. The 6502 can access any memory location in the entire 64K address range with a single instruction, without any need for setting up registers in advance.

    Running a typical instruction mix, the 500 KHZ 8008 processor executes instructions about 10 times slower than the later 1MHZ 6502 used in the Apple ][.

    SCEBLI progress

    June 17th, 2012

    Putting the CPU card aside for a while, I put some effort into the front panel card this weekend. First pass is already done, which is record time for a first pass. I guess all the work on the CPU card translated pretty well into basic layout and library stuff, which I could reuse.

    SCELBI Front Panel PCB

    SCELBI Front Panel PCB

    Next up will probably be the input card, which has a ton of complexity for a card with only 11 chips. Hopefully I can get a first pass of that card done in two weekends.

    First Lot of Super Proto Boards on order

    June 9th, 2012

    First, a little background.

    About a month ago, Rich Dreher tipped me off to an EEPROM issue he had seen in the past when interfacing an EEPROM to the Apple II bus. Well I didn’t have any issues with my prototype unit, but decided to do some additional testing with different EEPROMs. Back in the lab this EEPROM testing got confused with a flakey motherboard issue and the whole thing set me back a month.

    After moving to a different motherboard, I eventually figured out that ATMEL EEPROMs don’t play well with the Apple II address bus, just like Rich indicated. However, an alternate source, XICOR, makes EEPROMs that do seem to behave quite well, so I’m back on track. During initial bringup, I had done my original testing with XICOR, which is why I didn’t see the problem with ATMEL parts.

    So besides checking out EEPROM behavior, I made some design tweaks, checked out bus timing, made sure interrupts work and so on. At this point everything looks good,so I just pulled the trigger on a small trial run of boards. With any luck I may even manage to get some sent out to those of you HW hackers that are visiting K-Fest.

    I plan on completely documenting this board including the GAL online, so little to no printed documentation will be created. If I can figure out how to do it, I want to set up a wiki type documentation environment where prototypers can add their own designs and share their knowledge with everyone else.

    Here is the top side layout:

    Super Proto Rev 0

    Super Proto Rev 0

    The base feature set includes

  • Onboard 32K EEPROM – only 2K is normally addressable from Apple’s C800-CEFF and CX00-CXFF I/O space
  • EEPROM is programmable directly from the Apple II’s 6502.
  • Glue logic integrated in 22V10 GAL – replaces a number of 74LS glue chips that are commonly seen in designs like the super serial card and the mockingboard
  • Data bus fully buffered with 74LS245
  • PCB location for 6522A VIA, with no additional glue logic required
  • Two general purpose proto areas
  • Locations for more than 5 300 mill DIP chips of varying pin count
  • With 6522 VIA, room for an additional 40 pin dip package. This does cut into 300 mill DIP area. but it should be possible build a 3 channel Mockingboard on the super proto board.
  • Synthesized psuedo PH2 clock available – was required for 6522 inteface
  • The hope is that this board takes care of all the heavy lifting of interfacing to the Apple II bus and lets you focus on the the fun side of hardware hacking on the Apple II.

    Pricing hasn’t been set, but it will be well under $100 for a kit. Bare boards will also be available.

    Stay tuned.

    New Version of OS/X Scelbi Emulator Posted

    June 3rd, 2012

    Here is a summary of some of the main changes:

  • Mark Arnold (one of the original authors of SCELBAL) has fixed some mistakes in the version of SCELBAL I was originally using. These mistakes were introduced during the reconstruction of the program.
  • I have made changes to AS8 to support the RST instruction and my interpretation of how OUT port numbering should be implemented. If you are interested in this version, drop me an email.
  • The SCELBI expects that all inputted characters have the high bit set – and starshooter and SCELBAL have been reassembled to match. The power function such as 2^3 did not work in SCELBAL prior to this change.
  • The emulator itself now accurately counts cycles based on information gleaned from the 8008 data sheet. Each cycle takes 2 clocks and instructions take from 3 to 11 cycles. The emulator executes 250,000 cycles per second, same as an actual 8008. I should do some measurements using SCELBAL, but I’ve guessed that an 8008 might execute something like 30,000 instructions per second while running a typical program.
  • This version of the emulator uses port numbers to select serial or byte I/O, so the byte I/O menu has been removed. This effectively emulates a SCELBI with both serial and parallel (BYTE I/O) ports connected.
  • My 8008/SCELBI webpage can be found at this link-
    http://www.willegal.net/scelbi/the8008andScelbi.html

    Interesting Brain Board remote switch

    May 18th, 2012

    Corey Cohen came up with this easy method of creating a remote switch panel for the Brain Board. Here is an image of his prototype version. Knowing Corey, I’m sure that his final version will be mounted on a nice plexi panel.

    Brain Board Remote Switch Thingy

    Brain Board Remote Switch Thingy

    One DPDT switch controls which bank on the brain board is selected. Corey has loaded integer basic and the original monitor onto his second bank. The other SPST switch controls whether brain board or motherboard roms are selected after reset – this second switch is essentially the same as the firmware board toggle switch.

    One wire needs to be added to the back of brain board to connect Apples reset to the DIP socket at pin 2. Reset can be picked up from the onboard switch location. It is the center of the three holes.

    A ribbon cable is used to connect the remote switch box to the Brain Board. As you long as you stay within reason, longer ribbon cables than pictured should pose no issues. The only active signal is reset, which, when asserted, is held low for relatively long periods of time.

    Brain Board Remote Switch Setup

    Brain Board Remote Switch Setup

    Howard Cantin interview – Woz’s reaction

    May 8th, 2012

    See my earlier post describing my interview with Howard Cantin.

    I sent the excerpts of this interview to Woz to get his impressions. Woz was happy to see the interview and responded with some interesting comments. My email is indented and in gray, Woz’s response is not. This is published in my blog with Woz’s permission.

    On Apr 17, 2012, at 9:27 AM, mwillega wrote:

    Hi Steve,

    A couple of weeks ago I had a telephone conversation with Howard Cantin. Howard is known as the PCB layout person on the Apple 1. Apparently he was also involved in the first Apple 2 layout. A few of the things he said, are quite different than what I have heard and read elsewhere. I’d be interested to know what you thought of what Howard told me.

    My comments below.

    THANK YOU THANK YOU THANK YOU. It’s rare to find the true stories from back then.

    What follows are taken from notes taken during the call with Howard. The call was not recorded, so words are mine.

    Background
    Howard worked from his house for clients including Atari and Apple. Howard says he laid out all the boards for the first four years at Atari, until Nolan Bushnel sold the business. He also laid out first boards of other electronics startups in valley that became major players. Though he couldn’t remember the names of others, he says he did the first PCB for Intel. Howard says he was well connected to insiders in the valley electronics community and was the person to go to, when a PCB layout was needed. Howard related how he set many of the standards in PCB layout that were followed by others.

    Nolan Bushnell of Atari was often in a hurry and pushed Howard to hurry along a design. Howard says he was a fast designer, partly because of working under the pressure provided by Nolan. He could add a chip to a layout in hour.

    Steve Wozniak
    Regarding Steve Wozinak, Howard related to me, the often retold story about how Woz created a game design that used 60 parts instead of the 100 in the design that preceded it. Howard related that engineers at Atari couldn’t understand the design. Because they couldn’t understand it, Atari ended up not using it.

    How Howard Worked
    Most designs had an edge connector, so he would start with that and then add parts that connected to the edge connector. Then he would connect those parts to the parts that connected to those parts and so on. Vias were expensive and to be avoided, and would take up the space need for 3 traces. Howard provided his original artwork and photographic transparencies ready for the PCB manufacturer to his clients. Howard often didn’t negotiate price before taking on a job, but a typical cost was 6 to 8 dollars per chip. Howard worked directly from customers schematics, and is still proud of his ability to produce a result that matched the schematic perfectly.

    The Hobby Computer
    The first board that Howard did for Jobs and Wozniak was a computer to be sold to the hobbyists at the local computer club. Howard says that this computer was the board that provided the financing to start Apple Computer. Howard refers to this as a hobby computer, not an Apple Computer. Howard says the two Steve’s always were together and they conducted their discussions with him together. To pay for this computer, the Steve’s tried to trade an old Fiat Station Wagon for services rendered. Howard asked for cash, so the Fiat was sold and proceeds used to pay Howard. As some point, stock was offered, but this was also refused.

    The First Apple Computer
    Steve Jobs appeared to be a perfectionist to Howard. During the layout of the first Apple Computer, Howard had three proposed layouts with different form factors. There apparently was a lot of back and forth figuring out the form factor. Finally, Howard suggested one of the layouts happened to exactly match the size of a piece of legal paper (8.5×14) and Jobs selected that one. The proto area in the corner of this computer was empty and it was Howard’s idea to put pads for a chip and an array of pads that became the proto area.

    Though Howard did the main chip placement on this second layout, Howard paid a woman to lay the tape for traces. She was not very good and the traces she laid were not very straight. Jobs wasn’t satisfied and took the design and had it redone digitally. Jobs later told Howard that this re-layout cost Apple three months. Howard asked Steve why he needed to redo the layout and Steve said he was only going to do it once in his life.

    Howard did not use that woman for laying traces again. Howard told me that after that project, that he would have refused more work from Apple. In any case, Apple didn’t come back to him.

    PIRACY
    Howard also mentioned that he thought that the one of the Steve’s took a picture of an Atari board that he happened to be working on as the same time he was working for them. He thought that the Steve’s might have used this picture to duplicate an Atari design in some way. Howard did not have any specific details about what exactly was done with the image. Howard also said he talked on the phone with someone in England that might have been investigating another pirated Atari design. At one point, Nolan Bushnel asked Howard to pirate another design, but Howard refused. Howard now thinks that this was Nolan’s way of checking Howard’s honesty.

    Anyway I have these comments about what Howard said. I’d be interested in what feedback you had.

    He is confused about the “Hobby” computer that was the Apple 1 and the “first Apple Computer” that was the Apple II.

    When we met Howard at his home in Scotts Valley (I believe that’s where) we had not yet come up with the name Apple.

    Howard’s story says the vehicle sold to finance the Apple 1 was a Fiat Station Wagon, not a Volkswagon bus.

    It could be. It was some vehicle that really wasn’t being used as I recall. All I know is that I sold my most valuable possession, my HP-65 calculator, to come up with my half. Steve and I always did everything in business 50/50 (with regard to money).

    Do you remember taking the Apple II layout that was done by Howard’s subcontractor and then reworking it in a digital format?

    This does match my recollection, although the steps and reasoning for the switch to computer layout I wasn’t close enough to. I saw it being done but I don’t recall a negative reasoning, just that computer layout was ‘better’.

    Finally, his story of Steve Jobs and you somehow stealing an image of a Atari PCB and making some kind of profit from it. He was very vague about exactly what was done. That part of Howard’s story seems incredibly unlikely to me, especially given the inconsistantcies with the rest of the story.

    I would never do such a thing. I never photographed any Atari board nor remember it being done while I was around, but it’s possible that Steve Jobs did photograph one at some other time. I’m against stealing designs. Look at my designs, for example. You won’t find a bit of them extracted from some other design or data sheet. Check out almost every other hobby computer design around then and that’s all they were, duplicates of Intel data sheets. My design was always so original that it’s partly why Atari couldn’t understand it (Breakout).

    This story rings incredibly true and accurate, which is unusual in our business. Obviously it’s first hand from Howard and not filtered through communications types in companies or the media.

    Thank you for letting me know I’m not going crazy with all the things others have reported on these matters.

    — Woz

    Thanks and best regards,
    Mike W.

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