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What's a RIFA? (I have a feeling this is a really dumb question to ask).

The first Sparc CPU (V7) was the Fujitsu MB86900 in1986. This is the manual for the MB86901, which is also a V7. The introduction explicitly mentions a barrel shifter and later in the manual shifts are described as having 1 cycle...

I just threw that in. Many workstation applications were maths-heavy. An 8MHz ARM could beat a 16.7MHz SPARC for some DSP computations (mostly because multiplies were compiled as a library routine by default). True. ARM also had multiple load/store which could have helped 8bpp colour graphics...

Nice. Here's my video of my PS/2 to Quadrature-Encoded mouse conversion that I did for my 12MHz A3020 (6 MIPS). It shows me moving the paint tools palette around the screen along with the contents. You can also play with the Javascript multi-Archimedes machine emulator...

Although there may have been work in that area, it turns out the NeXT Step Dock (and Windows 95 taskbar) was derived from the first commercial implementation on the Acorn Archimedes' Arthur OS in 1987. (So, note, Arthur/RiscOS could drag windows around on a 4 MIPS ARM)...

Very impressive, and NASA plans to celebrate the occasion by sending 4 people on a Moon flyby :-) ! In just 40 mins... assuming they get the launch abort system battery issue sorted :-) !

On average I find that 1 line of code ≈ 10 bytes. So, 32kB ≈ 3200 lines, and at 50 lines per day(?) that's about 2 months solid coding. Yes. That's most of the difference, all the assets that form part of a modern application aren't actual lines of code written by a programmer. And there's...

Believable. When we were first put in front of the Mac 512s at UEA in 1986, they seemed very capable too. In fact, I've just remembered that in one of the introductory lectures in the first year, they were very excited to let us know that the Mac Lab Macs had been upgraded to 512k. That's cool...

@joevt , @Phipli : thanks for the replies. I've updated DumbDD so that I can specify the first sector (attached). All the sectors are assumed to be 512b and I'm assuming the sector size for Saved HD is 512b too. In my new test I set the first sector to 8000000 so in theory it would have...

OK, I'll add a Dd:Blocks... field to support starting blocks, then I can get it to read or write into the middle (or near the end) of the HD image and skip the APM. Though, actually it should indeed be possible to read the Apple Partition Map. TattleTech seems to work, I used it to get the SCSI...

It makes sense for it to have 2MB, given that the Mac 128/512 logic board can't cope with different types of RAM chips. So, initially I thought, yes it's going to be 128K (16x 64kBit), 512K (16x 256kBit) or 2MB (16x 1MBit). But the images appear to show 3 rows of at least 12 chips. My guess then...

I was able to 'recover' the Saved HD by restarting Safari, and do some more tests that involved copying about 6MB to it. Strangely though it never seems to corrupt the Saved HD itself, which puzzles me (I expected DumbDD to scribble over the HD making it unreadable). Actually it doesn't. These...

Interesting. At first I was confusing it with the 5260, whose display is limited to 640x480 and was the reason I bought a PM4400 instead, in 1996. And there's no corresponding 5360. Instead, the 5400 and 5500 kept the 52xx and 5300. Oh no, I've just been looking through EveryMac.com at all the...

@superjer2000 . The thing to note about a Sinclair ZX Spectrum is, of course, that it's really a 1bpp bitmap system with a 32x24 character resolution, colour attribute overlay. The Bitmap video is at address 0x4000 and the colour attribute overlay is at address 0x5800. Thus the primary...

'tis always the way. The principle of locality usually holds true, which means that most computation takes place locally. So a faster CPU with larger L1 and L2 caches improves performance. However, the big shift towards processing masses of media over the past few decades pushes the performance...

I'm actually very similar. I'd stuff a 5V, 8-bit AVR into anything I could. Partly, because I think like you it seems incongruous to design a peripheral that's far more powerful than the host. Anyway, sometimes I do use 8-bit PICs, here's the dumbest project I ever did, a PIC programmer built...