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Connect the Apple replica 1 to a serial port, launch Tera Term, configure the char and line settings, fiddle with the baud rate if data transfer is flakey, and we're off.
That's it (basically.)
I tested a couple of BASIC games, Rock, Paper, Scissors, and Checkers, or draughts as we call it.
As I've completely forgotten the rules for draughts I managed to eventually crash the game with an overflow error. Go* me - there's only so much error checking it had been programmed to deal with and an idiot wasn't in their game plan.
Phewee, it really doesn't get more exciting than this.
Next up, World of Wozcraft.**
* Go. That's a different game entirely, and not suitable for such an underpowered machine.
** Apparently that isn't a thing.
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There's a fine line between tolerating something and being offended by it.
Different people have the tolerance/offence line in different locations. How is it possible to present anything to any group of people without simultaneously infuriating some of those people who aren't 'triggered' by what is about to be presented but are 'triggered' by the mention of 'trigger warnings'?
Some of those people that are 'triggered' by 'trigger warnings' have provided a definition of the phrase here. At least it keeps those people all in one place, or perhaps it doesn't, I'm mistaking an online forum for some type of physical public location for containing debate.*
My suggestion is that we don't complain about trigger warnings, that we recognise that there are a lot of things in the world likely to cause offence, and that we can't pretend those things don't exist.
This argument clearly needs some development, so until then what I propose is that we use the handy device pictured below.
As well as being a Universal Counter Timer, it also has a handy "Trigger Level" control knob. The control knob can be used to effectively reset your own personal trigger threshold to either extreme, for example at the most sensitive level the use of the word 'knob' in a piece of text might bring the operator out in hives and cause smoke to come out of their ears.
Whereas if the dial is moved to the most insensitive level then a person could endure the most cretinous UKIPpy, Tory, brexity toss-wank possible, where it is plain that the speakers haven't got a 'Scooby-Doo' what they are on about or what they are going to do, yet the listener is as unmoved as if they'd spent the afternoon consuming a quarter of an ounce of Acapulco Gold until the smoke came out of their ears.**†
I think this is the most sensible solution for all involved. In anything.
* You know, like a forum.
** I have never experienced Acapulco Gold but the mellow is supposedly très mellow.
† It might be more appropriate to consume some EU barn-grown Dutch classic giant such as White Widow to 'trigger' the brexiters - I'd never heard of White Widow before, I looked it up purely for the purposes of making a cheap joke.
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On Saturday morning I plugged in the remaining IC's and tested the Woz monitor.
If you look on The YouTube you may see people plugging IC's into sockets as easily as plugging in a MagSafe power connector. Do not be fooled, a great deal of care needs to be taken in the preparation to have the IC pins aligned neatly with the socket. Make sure that there are no bent pins or pins out of alignment with the others, check to see far away from a close fit the pins currently are by offering the IC up to the socket. Use a firm surface to press gently all of the pins on one side at once slightly inward and keep alternating sides until the spacing of the pins match that of the socket spacing.
If a pin is already bent there is a good chance it will break, this may not be a problem if the wider part of the pin is still intact as it could still make good contact with the socket. If a pin breaks and there isn't good contact then push an off-cut piece of wire from a resistor into the socket and use that to connect to the IC, with solder if needed, although take care not to apply heat for too long here.
After assembling the final parts, shoes-off to prevent build up of static and component damage from electrostatic discharge (ESD), I reconnected the replica 1 to my monitor. It didn't work. I checked all connections again and nothing appeared out of place, I then realised I'd set the monitor to the wrong input type...
All was well. The replica 1 booted into the Woz monitor. The Woz monitor is the utility Steve Wozniak wrote to access memory locations, write to them and execute simple programs.
I entered these values from memory location 0300 using this syntax:
300: A9 0 AA 20 EF FF E8 8A 4C 2 3
Then I executed the hex code using the command 300R - 300 for the memory location to start from and R for Run.
It didn't work.
I set the caps lock on on the keyboard, entered the hex values again and executed the code from the memory location. This time it set off printing a continuous stream of characters as can be seen in the bottom image.
Apple 1 Basic can also be loaded from the Woz monitor, basic is included in the EEPROM chip. I'll get round to doing something with Basic later.
So far so good, nothing destroyed by standing on, generally clumsiness or ESD, the next task is to put it in some sort of protective container.*
* This is too easy, perhaps it would be an idea to build a replica machine from scratch.
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I spent Friday soldering components onto the the replica 1 plus board.
The replica 1 plus, designed by Vince Briel, is a functional replica of the original Apple 1. Vince's design was used in the book Apple 1 Replica Creation: Back to the garage. The book is available to download in PDF form here.
There are some optimisations in this updated design, these are mainly to reduce the number of logic IC's needed, in particular those IC's used for I/O. I/O in this design is catered for by the use of the large IC visible on the right in the picture below, the Parallax Propeller IC. The small IC next to the Propeller chip is a 24LC256, an industrial I2C EEPROM, often used in conjunction with a Propeller chip
Another modern addition is the USB to serial interface. This serves the dual purpose of powering the replica 1 and providing a built in converter to enable a serial interface to another computer to be made using a USB cable. If you've ever tried to use a serial-USB converter cable you'll understand why this is such an excellent feature - I have a skip full of converter cables with different chipsets that have all failed to work, your mileage may vary, but frankly they are crap.
The chip reduction is a nod to the techniques Steve Wozniak used to design the original Apple 1.
By the end of Friday the board looked as below but without the two IC's - prior to installing the Propellor and EEPROM chips I checked that each IC socket was receiving either 5v or 3.3v at the correct pins and that the ground pins on each were also working. Vcc (power in) and ground are not always in the same place and some browsing of datasheets was needed to locate the correct set of pins for each different IC type.
With the first two IC's installed the replica 1 can be hooked up to a monitor/tv and tested. The second image shows the expected output if the board is functioning, a screen full of garbage characters. The output is in colour due to the modern Propeller chip being able to generate colour output - garbage characters include colour as well as mono.
From bare board and bag of bits to assembly and first test on day one, no soldering errors, no broken components - result. The next step is to add the rest of the IC's and do further tests.
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I needed some sort of boot media while fixing a PC. The first thing I considered was a USB stick but unfortunately the PC BIOS was too old to support that. Ok then let's try a CD, do I have one?
It's interesting that it didn't really cross my mind to use a floppy disk, there probably are some in a box somewhere but would they even still be readable? I certainly couldn't have easily written to one as my PC doesn't have a floppy drive - I would anticipate a 'bzrrrr, grrrrrrr, whzzzrrrrr' sound from the read head struggling to access something resembling data if I'd had a drive available. You know the noise, the sound of 'data error reading drive A:'.
As it turns out I had a handful of CDR's, still sealed in their original packaging, but there was also a CDRW. Rather than open the antique TDK and SONY recordable CD's, that must date from the late 90's, I opted for the CDRW. Let's see if this magical item, which had a brief moment in the sun at the turn of the century before USB sticks became a decent size, would function.
The CDRW was easily formatted and had a bootable ISO image written to it and booted an operating system to recover the stricken PC, and that was that for a walk down memory lane.
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It never occurred to me that dogs could become seasick, but then I've never been at sea with a dog.
Some of the dogs that sailed with Sir Earnest Shackleton on board Endurance were treated for seasickness, and with what appears to be the same bottle of patent remedy that any other member of crew would have used.
Here's a dog having a healthy glug of remedy poured into it and not appearing to like the taste.
If only the dog had known it would have to eat seal blubber for the next 9 months it might have asked for some of the remedy to be saved to wash away the irony taste.*
* Although I expect dogs might actually like the irony, gamey flavour of seal meat.
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Question 1.
Write 450 words on the use of controlled feedback as a thematic device in Boston's More Than a Feeling
Question 2.
The cowbell used in the recording of (Don't Fear) The Reaper by the band Blue Öyster Cult has become an internet meme. Discuss in 250 words why April 2000 and July 2004 are relevant, making particular reference to the actor Christoper Walken.
Question 3.
Discuss the impact of the Neil Young song Heart of Gold on the work of Douglas Adams and whether or not it has any relevance. Use no more than 150 words.
Question 4.
The Janis Joplin song Piece of my Heart refers to a part of human anatomy, which piece of that particular part of human anatomy is responsible for the third verse? Express your answer using De Morgan's laws, write no more than two lines.
Question 5.
The image below contains a reference to the popular recording artist Nancy Sinatra, explain the reference and its relevance using a prime number of words beginning with alternate letters of the alphabet only, be sensible in the length of your answer.
Hand in your finished question paper to Mr Sumner, but don't get too near.
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