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Comment Re:The publisher refuses to take my money (Score 1) 164

How does it hinder it in these particular cases? The things you listed aren't exactly classics.

Who decides what are "classics"?

Find me a lawfully made copy of these on a video format popular in the United States.

So buy it on DVD

From the linked page: "Region: Region 2 (This DVD may not be viewable outside Europe. Read more about DVD formats.)" Region 1 DVD is popular in the United States. Region 2 DVD is not.

Comment Re:Super NES address space is far from linear (Score 2) 160

Different aspects of mirroring have different purposes.

Mirroring is the result of incomplete decoding of the address bus. Incomplete decoding saves a gate or two and usually doesn't hurt anything. Shaving pennies off the replication cost of millions of Game Paks could increase profit.

The 65816 requires the reset and interrupt vectors to be available at $00FFE0-$00FFFF in order to start up. If ROM is not mirrored into $00FFE0-$00FFFF, the system will hang at startup.

Only ROM at $808000-$FFFFFF is set up for fast access. The rest of ROM ($008000-$7DFFFF) is hardwired for slow access so that the 65816 can retrieve its reset vector before the memory controller is configured. So programs run memory controller initialization somewhere in $000000-$7DFFFF and then jump to $808000-$FFFFFF once they've initialized the memory controller.

I/O and a portion of RAM are mirrored into $00-$3F and $80-$BF so that the CPU can access a subset of data in ROM, data in RAM, and I/O without having to either change the data bank register or use 24-bit addressing all the time. Unlike the 8086, the 65816 doesn't have "prefixed" instructions that can change which segment is used. Instead, the data bank register must be explicitly reloaded in order to use 16-bit addressing, which is slightly faster than full 24-bit addressing. In addition, several 65816 addressing modes are hardwired to use bank $00, particularly those dealing with the base pointer (D) or stack pointer (S).

See Fullsnes or Super NES Development Wiki for more information

Comment AWS is cheap but not free (Score 1) 141

Video at 720p takes about 2 Mbps (source), or 2 Mbps * 60 s/minute * 1 GB/8000 Mbit = 0.015 GB/minute. Data transfer out of AWS costs 9 cents per GB plus tax (source). If a 10-minute (0.15 GB) video goes viral (which used to be called getting Slashdotted) and gets 10,000 views, that could result in a big AWS bill: 0.15 GB/view * 10,000 views * $0.09/GB = $135. Is the average person expected to afford that without running his own ads?

Comment Super NES address space is far from linear (Score 4, Informative) 160

The part of the Sega Genesis memory map allocated to the cartridge is a linear sequence of bytes from $000000 to $3FFFFF. The part of the Super NES memory map allocated to the cartridge is not. See my diagram of Super NES address space.

The 65816 divides its 16 MiB address space into 256 banks, each 64 KiB in size. In order to make certain addressing modes more efficient to use, the Super NES divides up cartridge ROM address space as follows:

  • Bank $00-$3F: Second half (32 KiB, $8000-$FFFF)
  • Bank $40-$7D: Whole bank (64 KiB, $0000-$FFFF)
  • Bank $80-$BF: Second half (32 KiB, $8000-$FFFF)
  • Bank $C0-$FF: Whole bank (64 KiB, $0000-$FFFF)

The "HiROM" mapping (mode $21 or $31) is a linear sequence of bytes from $C00000 on up. Because of incomplete decoding of the address bus, the second half of each 64 KiB bank is usually mirrored into $808000-$80FFFF, $818000-$81FFFF, $828000-$82FFFF, ..., $BF8000-$BFFFFF. In addition, banks $80-$FD are mirrored into banks $00-$7D, so that the 65816 CPU can find the reset vectors at $00FFE0-$00FFFF (which is mirrored from $80FFE0-$80FFFF). Usually, battery save memory is at $306000-$307FFF, $316000-$317FFF, ..., $3F6000-$3F7FFF.

You might notice that everything in the above skips banks $7E and $7F. That's where the Super NES puts its 128 KiB of RAM, with the first 8 KiB mirrored into banks $00-$3F and $80-$BF. It also mirrors the memory-mapped I/O ports associated with the CPU's memory controller and the Picture Processing Unit (PPU) into banks $00-$3F and $80-$BF. They are made accessible through all these banks so that the same value of the Data Bank Register (DBR), analogous to the Data Segment (DS) register on 8086, can see RAM and ROM at the same time.

The "ExHiROM" mapping (mode $25 or $35) has two linear sequences of bytes: from $C00000 to $DFFFFF and then from $400000 to $5FFFFF, which get mirrored down into the second half of $80-$BF and $00-$1F respectively. Only the largest games, mostly exclusive to Japan such as Tales of Phantasia, use ExHiROM.

The "LoROM" mapping (mode $20 or $30), more common on early games, does not connect A15 out of the system to the ROM. This means it uses only the second half of each bank: $808000-$80FFFF, $818000-$81FFFF, $828000-$82FFFF, ..., $FF8000-$FFFFFF. Banks $C0 through $FF mirror the 32K of data in that bank into both halves of the bank, and banks $00-$6F are a mirror of banks $80-$EF. Usually, battery save memory is somewhere in $700000-$77FFFF.

Cartridges use either slow or fast mask ROM. Modes $20, $21, and $25 are "slow ROM", where the CPU slows down slightly in order to allow use of cheaper 200 ns ROM. Modes $30 and $31 are "fast ROM", which needs 120 ns ROM that was more expensive in the early 1990s. Mode $35 has fast ROM for the $C00000-$FFFFFF region but slow ROM for the $400000-$5FFFFF region.

Slight differences in address decoding in each cartridge lead to differences in which address ranges actually contain mirrored ROM (as opposed to open bus) and which address ranges contain battery-backed RAM. Furthermore, some coprocessors included in cartridges can change this mapping at runtime.

Comment Re:The publisher refuses to take my money (Score 1) 164

Then you are not ENTITLED to watch it

How does this lack of ENTITLEMENT "promote the Progress of Science and useful Arts"?

Wait a few more years and it will all be worked out

This is not practical for copyright, which is designed to subsist for a period exceeding one human lifetime.

Comment The publisher refuses to take my money (Score 2) 164

Today with all the options available 'because I can't get it any other way' is a crock

Sometimes I can't get it because the publisher refuses to take my money. Try this exercise: Find me a lawfully made copy of these on a video format popular in the United States.

  • The TV series Spartakus and the Sun Beneath the Sea (the English-language dub of Les mondes engloutis)
  • The film Song of the South (Unless you think LaserDisc was "popular")
  • The film Pinocchio and the Emperor of the Night (Do you consider VHS still a viable option?)

Comment Re:linux (Score 1) 90

Which make and model of phone runs GNU/Linux? If it's the one I think you're talking about (Nokia N900), it's probably "a mythical beast" in Slashdot's home country. Can it even connect to modern networks now that AT&T is phasing out GSM service in favor of expanding LTE?

Comment Free market for unlocked phones (Score 1) 205

Its not a free market anywhere. The radio spectrum is very limited.

I thought there was a free market for phones that work with any major carrier's spectrum license, especially now that all four major U.S. carriers use LTE. LTE is patented but, as far as I'm aware, licensed under a uniform royalty regime.

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