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20

Yes. For example, the Xircom PE3-10BT is a parallel port adapter that allows an RJ45 connector be plugged into it. You don't get full 10 Mbps with it, but it works. Mine is powered via a PS/2 port passthrough plug and jack. I use mine with my 386 laptop.


20

The Am386 and Am486 were designed as clock-for-clock equivalents of the corresponding Intel CPUs, based on reverse-engineering and AMD’s previous second-source licenses — at least the Am386 even used the same micro-code as Intel’s 80386. The only speed advantages came from higher clock speeds (40MHz v. 33MHz) and, in some Am486 models, the use of write-back ...


16

Software can identify those early steppings on the 386 by checking whether the XBTS and/or IBTS instruction can be executed, since these instructions were dropped in later chip revisions. Software must, however, first check whether the CPU is really an 80386 and not 486, because the some early steppings of the 486 temporarily re-used the opcodes of these two ...


14

The daughterboard is the graphics card. The GD610/GD620 is a quite common chipset for LCD/VGA graphics in laptops. It uses two 64k x 16Bit RAM chips to obtain 64k x 32Bit, which is the usual VGA memory (256 kBytes, but the VGA needs 32-Bit access to get the data fast enough to the screen). Those RAM chips have an access time of 100ns. The chips on your ...


13

No, this sound card is definitely not intended for such a slot that expands the ISA slot to 32 bits. This is a Compaq-specific sound card meant for a Compaq-specific ISA slot extension. There is no more than the six pins for Compaq-specific audio extensions. Based on a few pictures of the card, it simply routes some audio signals between card and backplane. ...


13

If you have another computer to hook it up to and act as a bridge (or router), you could in principle run SLIP or PPP over the serial port to another machine. You're unlikely to get speeds exceeding 100 kb/s.


12

I’ve wondered about this for a long time — manufacturers don’t seem to communicate FPU transistor counts as readily as CPU counts. The best I’ve found so far is a claim on coprocessor.info that the 80387 contained approximately 120,000 transistors (quite a bit more than the 8087’s 45,000 transistors).


11

Since it's a pretty early laptop without a PCMCIA port, there won't be a way to add an Ethernet port. Your best approach is to use the serial port to connect via null-modem cable to a modern machine that either has an RS-232 serial port, or has hardware and drivers for bridging its USB port to RS-232 serial. Once the two are connected, use of the laptop as a ...


10

Is it really so simple as just getting to higher clock speeds than Intel did? Yes, it is that simple. Up and including the 486 AMD's CPUs were developed close to Intels devices, supported by in detail information provided by Intel as well as reverse engineering. AMD adapted the design to their production process. This included low level changes in how ...


10

Well, it could easy be a socket for a 387 type FPU. Size and number of pins would fit a 387 (or some pin compatible Cyrix FastMath) as PLCC carrier. On the other hand it's rather unusual to place it far from the main CPU, seen in the lower left. But without more information it's hard to say. Maybe some sharp close up can reveal markings supporting this?


9

Were those slots manufacturer-specific or was there some kind of (unofficial) standard? Manufacturer specific. (Well, there was EISA, but I guess it's safe to assume that this question is explicitly not about EISA) What additional signals were available in these slots? Most likely D16..31 and A24..31. Plus maybe BE0..3 - and that's where the main issue ...


7

One option is to use a modern Linux board to act as a fake modem connected to serial port. Then you can use any old software that would connect to internet by a modem connection, without actually having to pay the massive phone bills of the 1990s. The software setup is not very complex, mainly requiring installing ppp server on Linux. There is also a ...


6

The 32-bit extension to ISA was Extended ISA but it doesn’t add any additional connectors, instead adding extra pins to the part of the existing edge connector that is reserved for insulation.


5

It's not a completely robust answer, but I found the following text archived at Computer Business Review from March 1987 that's primarily about Zenith's plans: In the UK, 27% of Compaq’s revenue comes from its 80386 The Compaq Deskpro had originally been announced only six months before that article, in September 1986. So based on the timeline: a 386 was ...


4

Since there is no documentation available, all ways I can think of to check ahead of soldering would involve a certain level of measurement devices - like logic analyzers or at least a digital oscilloscope - which I assume are not present. So I'd simply go ahead and pick four 424400-80 (or compatible), solder them on (not forgetting to add appropriate ...


4

You are getting everything wrong. The 286 has integrated segmentation unit and protected modes to allow multitasking OSes and more memory (up to 16MB). It was actually used for that purpose in early versions of OS/2 and Windows. The definition of "workstation" is arbitrary. 640kB DOS was becoming cramped, and the 286 allowed to use more memory. The ...


4

You question says that the UK computers were produced only to fill 'a niche' left by the U.S. computers but that's not the case. These were large, wide-open markets at that time. The BBC micro, for instance, was a attractive product with better capabilities than the Apple II: faster, better screen modes, better BASIC, better OS. The ZX80 and particularly ...


3

Normally you would enter the parameters in for a custom drive. Normally you would also have to figure out what native CHS parameters for the CF card are so you can type them in or select one of existing ones that match best. As no existing type is nowhere near 500MB, you can't utilize the card for 500MB unless you type in custom parameters. As it is a 4GB ...


3

Assuming you're looking to put your laptop on the internet as opposed to just do file transfers or some such, there are a couple of DOS TCP/IP stacks. If you're lucky, you can find one of the Xircom PIO ethernet controllers. More likely, you'll do it over the serial port. You're looking for an IP stack that supports SLIP or PPP, which are IP-over-serial ...


2

It can be tested by performing various multiplication operations and verifying the result. List of such code that performs ten tests with various memory and register based operands is available for example at pcjs.org, but as others have already pointed out, the problem may only manifest under certain conditions and can depend on e.g. CPU supply voltage, so ...


1

If we want to talk about the formfactor and not necessarily have the device be called a tower, I would say the MacSE(1984) could make an interesting case study (pun intended). Although it could be argued it was more akin to the portables of its time but in a vertical orientation rather than a horizontal one. Portable/luggables still needed to be plugged into ...


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