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Lesse, I see an Atari 2600 joystick, an ellipses poster, a cricket bat, a TV and/or old monitor (with convenient handles!), an unknown computer system (Amiga?), Christmas lights, VHS (or BetaMax?) tape…

Also, hi Ravi.

Commodore 64 monitor, betamax tape, and a TI-99/4a! :)

I’ve had pretty much all of those at one time or another… I’ve had a TI-99/4A, Atari 800, VIC-20, Commodore 64, Timex/Sinclair 1000, Apple IIe, etc., at one time or another.

I still have two Commodore 64’s in my closet, both of which still work, and two 1541 disc drives (also both working). Though it’s anyone’s guess if my collection of floppy discs still work after all these years. Even in a climate-controlled, dark closet, those magnetic disks have a limited lifespan.

How much time has elapsed between chapters? Michelle’s inner glow appears to have gone.

Something also tells me Martha isn’t responsible for this.

Why do I now feel this happened during their hike to the catacombs?

If so, than the big power switch in the off position means that the catacombs don’t have the lights on.

Am I wrong, or is that switch is upside down for British standard?
Up is off. Down is on.

What, no Spectrum? Real Liverpudlians would have had a rubber-keyed Speccy in there. :)

This is 2005, not early 1980s.
But yeah, why WOULD they have had a TI instead of a Sinclair ZX Spectrum or BBC Micro ?
Back in the early 1980s, I had a ZX81, board issue 1, rev 0, 5 chip. I was jealous of folks who had Spectrums.

The simple answer is I had a TI-99/4a as a kid and I wanted to draw it. I think y’all are obsessing a little too much over the little details! I don’t research THAT deeply haha.

Not obsessing Kory.
Back in the 1980s, UK National Pride meant that in Commonwealth nations the BBC and Sinclair were heavily promoted.
Those 2 UK microcomputers were going toe-to-toe with the US majors Commodore, Apple, Radio Shack, and IBM.
It wasn’t till the mid 1980s that Amstrad launched the CPC464.
Here in Australia, the sole entry into the microcomputer market was the Microbee, but it was never promoted with as much National Pride as the US or UK brands.

Hmmmm…. Martha’s collar has an interesting shadow– not a collar-shaped one, more of a blob. **ponders** Maybe she only keeps to her dogshape as a spirit when she’s visible?

Yay skin deep is back. Loving the new page. Though I am still gonna be abit picky lol. I am sure you agree Jenniskunk that the light switch is the wrong type, but the plug for the VDU is nearly correct, except the pins are upside down.

Copying my reply to ThisFox about the light switch, from earlier in the comments.

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Upside down, I’d say.

I think this the type of lightswitch in the basement.
http://www.acornengineer.co.uk/brass-plate-chrome-dolly-toggle-switch-on-off
It looks to be a rectangular mounting, rather than the standard UK square.
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Never saw a UK issue Commodore 64 monitor here in Australia, so I’ve no reference as to how the pins are set on the power cord.

What bugs me about the new page is how deformed the tenpin bowling ball is.

That wasn’t the intention about copying you Jeniskunk, I just hadn’t read all of the comments at this point, whilst hiding in a place, while at work and reading them on my mobile phone.

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Deffo upside down.

with this being how they should look, though naturally with the wire coming out of the bottom
http://www.quadtronics.co.uk/13-amp-3-pin-plug-94-p.asp

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Oddly enough I’ve never seen one either. When I used to have a C64 many years ago, I used it on a regular 14″ portable tv. Damn where has time gone, when it took 7-14 minutes to load a program from a cassette tape!

The long time to load a program was a side-effect of having the most reliable tape recording method of any 8-bit computer. On most of the C64’s contemporaries (Atari 800, TI-99/4A, etc), if the tape recorder was a little fast or a little slow or the tape stretched just a little bit (or sometimes even if the volume knob had been moved), there was no guarantee your program would load. The VIC-20 and C64 never had that problem.

I could get technical and actually describe the tape format, but I won’t. I’ll just say that it saved the program twice, and would compare the second copy against the first to detect errors. So it was ultra-reliable… and ultra-slow.

Did the other formats have something like CRC?

It depends on the computer. For example:

(1) The TI-99/4A began with 768 zeros in a row as a sync marker. Then the data was divided into 64-byte blocks. Each block would begin with a sync marker of 8 zeros, followed by 64 bytes of data, followed by the LSB (least significant byte) of a two-byte simple checksum (not a CRC… it just added all 64 bytes together into a single 2-byte integer, then wrote the LSB of that integer to tape).

It wrote each block to tape twice in a row, so if you could look at it physically, it would have block 1, block 1, block 2, block 2, block 3, block 3, etc. If the checksum didn’t match the first time, it would try to correct it by reading the second copy of the data block. If the checksum DID match, it would ignore the second copy.

(2) The Atari 400 and 800 used 128 byte data blocks, and did not save two copies. The main difference was in the encoding… each byte began with a start bit, then 8 data bits, then a stop bit. Each block began with two sync bytes, a control byte, 128 bytes of data (encoded as described above), and a single checksum byte. Then there was another three-second “mark tone” before the next data block started.

NOTE: One oddity about the Atari 400/800 was that it wrote out the bytes least-significant-bit first, while every other 8-bit computer of the time wrote them out most-significant-bit first. Also of interest is that the Atari was the only 8-bit computer that saved data to disk in 128 byte blocks… everybody else, and I mean everybody else, used 256 bytes.

(3) The Apple II… I’m not sure how many bytes per block it used for tape files (for disk files, it used 256 bytes like almost every other home computer at the time). At least it XOR’ed each byte of the data block with the checksum as a crude form of parity.

Here’s the important difference, though, between all those computers and the Commodore format:

All the other 8-bit computers used an analog tape format. The Commodore computers used a DIGITAL format (which is why they wouldn’t work with just any old tape recorder). Each data block was 192 bytes long, and the load routine was so reliable that you only got a ?READ ERROR if there were more than 30 errors in the first copy, or errors that couldn’t be corrected from the second copy.

The catch? Well, it was slow, unless the program was saved with a high-speed tape loader like TurboTape (published as a type-in program), which sacrificed reliability for speed. I seem to recall a top speed of about 50 bytes per second. The Atari 400/800, Apple II, Sinclair Spectrum, etc., were about three times faster… an average of 1500 baud (about 180 bytes per second).

Oh, by the way, the TI-99/4A was *not* an 8-bit computer… it was actually a 16-bit computer, with a TMS9900A CPU clocked at 3 MHz, BUT only the system ROM and 256 bytes of “scratchpad” memory were available on the 16-bit bus. All other memory (such as the 16 KB of graphics RAM) was connected to the CPU through a 16-to-8-bit multiplexer, requiring twice the cycles for any access and introducing an additional 4-cycle wait state.

On top of that, the built-in BASIC used the graphics RAM, accessed a single byte at a time through a dedicated memory port. Not only that, but when you ran your BASIC program, it was interpreted into GPL (Graphics Programming Language) and then interpreted again into machine language.

All computers of the time used BASIC as an interpreted language, not a compiled language. But TI-BASIC was the only one that was double-interpreted like this, making the TI-99/4A paradoxically the fastest (because of the 3 MHz 16-bit CPU) AND the slowest computer of the era.

Also, a lot of its advanced features (like 32 hardware sprites) were simply not available in TI BASIC. Anyone who was serious about programming their TI-99/4A installed an Extended BASIC cartridge and 32K RAM Expander (or “piggybacked” extra RAM by soldering chips on top of the 256 byte “scratchpad” RAM).

The TI-99/4A still has a cult following in the vintage enthusiast market… which is still inventing new hardware upgrades such as an USB card and an IDE drive controller.

Anyway, the only reason for this post was because I mentioned “all the other 8-bit computers” and I knew that someone would call me out on it, because the 99/4A was 16-bit…

I think I’ve just found a couple of continuity bugs.

The light switch James uses, should not have turned on the hanging light in the basement.
Page 7 of chapter 1 shows the hanging light as having a pull cord switch.

Page 7 shows lights on a power cable being on the characters right coming from the door to the caverns, left going to the door.

On this page, the knife switch and power cable going into the caverns is on the characters right, same side as it comes out of the doorway into the caverns proper, on page 1.

So the light switch James flicked should have turned on the lights shown on page 7 to that doorway and not the hanging overhead.

page 7
http://www.skindeepcomic.com/archive/illumination-page-7-the-basement/
page 1
http://www.skindeepcomic.com/archive/illumination-page-1/

edit: further to the continuity bugs, page 7 of chapter 1 shows NO lightswitch existing for James to have turned it on, on this page.

what’s up with the 3 dots. I know there’s something up with them but that? it’s driving me cray cray. is it a reference to the constellation of orion? but if that’s true what’s the 4th dot above the piece of paper that has the 3 dots on it?

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