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Apple IIc As a Battery-Powered Portable Computer

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Apple IIc was designed to be portable. That meant that the computer could be easily carried from work to home or anywhere else where you had a power socket and a composite screen (or TV). I knew about the LCD option offered by Apple but I didn’t know that there were complete kits to make the computer usable everywhere.

A true mobile user could enhance his Apple IIc with a passive-matrix non-backlit LCD (connected to the video port using a ribbon cable) and an external lead acid battery. There were also bags specially designed to carry all this stuff safely.

This option was not very successful, though. Not because of its weight around five kilograms – that was adequate by the standards of the era (there were people carrying Osbornes). The main problem was the LCD screen which could produce a good picture only under direct sun light. The contrast was extremely low and the screen was hardly readable in a dimly lit room. I’ve tried few different laptop LCD screens from the same generation and my eyes almost bled after 30 minutes of work.

Having three separate parts was also not very convenient for frequent travelers. The screen was not designed to cover the keyboard when the computer was being transported and you always had to attach the battery. The first generation of laptops started to appear at the same time. Although they were as heavy as this kit, they had all components in a single briefcase-like package. In 1985, you could buy Bondwell Model 2 (a cheaper CP/M laptop with 64kB of memory) or one of those PC compatible laptops which started to appear at the end of the year (like my Bondwell Model 8).

Image sources: imgur.com, popcorn.cx

Hard Times With UNIX

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We have three SGI Octane2 workstations in our “lab” but none of them were in the ready-to-use state. I’ve decided to take a look on the one which looked like it could work (the only one with hard drives). Already installed IRIX was somehow corrupted and was accessible only by using a serial terminal. I realized after a few hours that the original installation couldn’t be fixed with my knowledge although the hardware (graphics card) was ok. The only way was to install a fresh IRIX.

I used a laptop with a serial terminal emulator instead of local peripherals and SGI O2 as a server containing all the installation files. For the first time I used BOOTP and TFTP to boot a computer over network. I was surprised how easy it was. The former (BOOTP) is intended to get a boot program to the memory of a target computer (to be executed then). The latter (TFTP) is intended for simple file transfer. Good thing is that you don’t need properly configured Ethernet interface to get this working. A server just needs to know the MAC address of a client and a file to be sent.

It took me more than ten hours but I have one fully working Octane2 now. Surprisingly, booting and accessing all files over the network was the easiest part. Most of the time was spent on identifying the initial issue, “package dependency hell” (typical for UNIX systems) and the fact that the IRIX 6.5.22 boot file didn’t work. I had to start with IRIX 6.5.5, install a special patch and then install IRIX 6.5.22 (which correctly recognized all the hardware inside Octane2).

It was definitely an interesting experience… but I hope I won’t need to do this all again soon. Anyway, for a moment I felt like a real UNIX geek.

Inside the SGI O2 UNIX Workstations

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SGI O2 was designed as a small low-cost workstation. This is clearly visible on its internal hardware architecture with unified memory shared between the graphics chipset, CPU, and add-on video grabber. I like the smart design of the case. Everything is easily accessible (except for the CD-ROM drive which needed to be fixed). You can replace the mainboard or hard drives quickly and without any tool.

Btw two of the three mainboards are alive so at least two machines will work. Two working boards are equipped with 180-MHz MIPS R5000 (one in a version without L2 cache). These CPUs were the lowest available options.

New SGI Stuff Directly From SGI

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SGI guys are moving to an HPE office building so I’ve visited them to take some junk that would be otherwise thrown away. I took one SGI 320* and three SGI O2 workstations plus few small industrial (non-SGI SGI-branded) computers. There was a lot of old hi-end servers, JBODs, FC switches, NUMA link boxes and so on but the storage capacity of my house is limited so I had to let them there.

*) It’s one of their first x86-based visual workstations. It’s not PC compatible and its architecture is similar to O2. The only supported OSes are Windows NT 4.0 and Windows 2000 and you need a special loader to get Windows running on this system.

Expanded Sinclair QL

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This is my Sinclair QL setup. It is 0.9 meters wide when a 512kB RAM expansion, floppy controller and floppy drive are connected. You need a really big desk for this.

Sinclair QL, Motorola 68008 and Microdrive

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A friend of mine sent me one Sinclair QL in a big box with manuals and accessories (ROM modules, floppy controller, IDE controller, 512k RAM expansion, RS232 adapter) because I wanted to test it using our benchmark and compare the results with 8088 in PC and Motorola 68000 in Amiga 500.

Sinclair equipped the computer with Motorola 68008. The standard 68000 CPU has a 16-bit data bus, but this smaller version has it only eight bits wide. The rest is the same so there are 32-bit CPU registers and 16-bit ALU. Using the narrowed data bus was an understandable way to make computers cheaper. IBM PC 5150/5160 has also its data bus eight bits wide. On the other side Intel 8088, unlike Motorola 68008, has a small prefetch queue so there should be smaller performance loss in comparison with a standard version of the chip.

I’ve never done anything with Sinclair QL so this is my first time. I’m quite surprised that the keyboard is mechanically much better than the one on Sinclair Spectrum+ (which looks almost the same). Also two integrated Microdrive units are easy to use and surprisingly fast. Each tape can hold 100kB of data and having two drives allows for easy tape copy.

Atari STacy 2 (1989)

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It would be a shame to not share the rest of Atari STacy photos. This was my first experience with this machine and it was wonderful. The large trackball is a pleasure to use and the only thing I don’t like are small arrow keys.

The machine is in perfect condition (the display is less bright though). Its internal 640×400 1-bit monochrome LCD operates in the ST High mode and it doesn’t support any other mode. You can use STacy for playing games but you need to attach a TV set or a color monitor then.

You’ve probably noticed that there is a battery LED indicator. The machine doesn’t have a battery (other than the one for RTC backup) because Atari was not satisfied with a very low battery life and decided to not include it (in order to lower the price).

Beware of Dead RTC/Backup Batteries (Again)

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It took me half a day to get mostly dead RTC and RAM backup batteries from two desktop and six notebook computers. In 50% of cases the batteries already started leaking so they would soon kill the computer.

I didn’t replace the batteries with new ones as I don’t need another ticking bomb in my old machines. Now I have to access BIOS setup every time I want to use the computer. That’s the only drawback but I can live with it.

SyQuest Removable 44MB HDD Connected to Atari TT030 Using SCSI

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It is fascinating that the drive works flawlessly even with a lot of dust inside (unlike with normal hard drives, the reading head is not in a clean air environment here). This particular drive was used to transfer large files between computers in a DTP company. It is fast and reliable. On the other side its price/capacity ratio was not good in comparison with normal hard drives so it was not widely used.

X86 vs. ARM

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We had a discussion about performance difference between IBM PS/2 with 20-MHz 386DX and Acorn A4000 with 12-MHz ARM in both Basic* and assembly code. David started to write code on A4000 and although I like the hardware, that British sense for user interface design would prevent me from being happy with this machine.

*) BBC Basic vs. MS QuickBasic