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You're right: many of TecToy's Brazil-exclusive Master System games were tweaked versions of Game Gear releases. That includes games like Ecco 2, Mortal Kombat 3 and Sonic Blast, but not the aforementioned Street Fighter II which they developed independently.

I think the Master System version of Sonic Spinball came from Sega themselves though. It was sold in Europe as well as Brazil.


> On execution, 16-bit Thumb instructions are transparently decompressed to full 32-bit ARM instructions in real time, without performance loss.

That quote is from the ARM7TDMI manual - the CPU used in the Game Boy Advance, for example. I believe later processors contained entirely separate ARM and Thumb decoders.


Throughout the entire NES game library, almost no games use these illegal opcodes. Apparently as part of the licensing process, Nintendo would verify that games only used the official instructions.

I wonder how they tested that, though? I don't think developers had to submit their source code to Nintendo, so they would have had to analyse the binaries in some way?


> I wonder how they tested that, though?

The QA process might have been performed on an emulator that doesn't support illegal opcodes.


I don't know if they even had an emulator at the time - I don't think a 1980s PC could run a NES emulator at a reasonable speed.

Another possibility is that they used a hardware device. Perhaps something that watches the 6502 `sync` pin to know when an opcode byte is being read, and verifies that the data bus contains a legal value.


> Link's Awakening feels like it shouldn't be possible in a single megabyte of mask ROM

Half a megabyte, even! (For the original monochrome game - the later color version is a full megabyte.)


Ah, right, I fortunately slept on it long enough to get the DX version right away! The photographer side plot was amazing, especially with a Game Boy Printer :)


220uF is correct. Along with the 75Ω terminating resistor inside the TV, that forms a high-pass filter with a cutoff frequency of ~10Hz.


Nice and compact! When I was writing a Z80 emulator I made heavy use of the tables in Sean Young's "The Undocumented Z80 Documented" [0] (chapters 8, 9 & 10). This 2-page reference card seems to contain just about everything in the document's 22 pages.

[0] https://www.smspower.org/uploads/Development/z80-documented....


> no instruction timing chart?

Instruction timings are in the pink table on the left-hand side. For example, `ADC HL, BC; ED4A; H15` means that the instruction affects the flags as in row H and takes 15 cycles to execute.


Yeah, you're right, and I totally missed that on my first scan, probably due to being blinded by the huge hex conversion chart...


> Sony’s part number suggests it has a 45 inch tube inside. But in a rare case of truth in advertising, Sony advertised it as a 43-inch model.

The overall tube size is 45”, the actual screen size is 43”. I believe it was mandatory in the USA to market TVs based on screen size, in most of the rest of the world they were sold based on tube size.

That’s why common sizes of 4:3 CRT TV in the US were 13/20/24/27/32” whereas in the rest of the world the same size TVs were sold as 14/21/25/29/34”. Interestingly the tubes’ internal part numbers are based on the screen size in centimeters: 34/51/59/68/80 cm.


According to [0], about 1.2 kg (2.6 lbs). Surprisingly this is mostly in the neck and funnel of the tube - the screen itself uses different metals because lead would affect its optical performance.

[0] https://www.sciencedirect.com/science/article/pii/S187802961...


Yes, the aperture grille (hundreds of wires and a metal frame holding them in tension) is itself heavier than a traditional shadow mask.

However, aperture grilles also use differently-shaped glass from shadow masks. The screens are only curved horizontally like a cylinder rather than on both axes like a sphere. This requires thicker, heavier glass to hold the vacuum.

Later flat-glass shadow-mask tubes were much closer in weight to flat Trinitrons.


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