Well, it did do a lot for you. And the large RAM with flexible descriptor tables meant that in practice, you could avoid doing too many writes over to the VDP most of the time. And, the separate dedicated-RAM architecture does guarantee no cycle stealing, unlike, say, the VIC and VIC-II chips in the Commodore computers, or the need to wait for horiz/vert refresh to avoid "sparkles" like the old CGAs.
Let's face it, all these old computers were an exercise in tradeoffs.
I see the spot/crosshatch pattern on car windows when I wear polarized shades. I don't see Haldinger's brush, though, when I'm wearing no glasses. The pattern on car windows comes from the glass-tempering process.
Actually that's a good question: since you see UV light, could you use a UV flashlight to walk around in what appears to be almost complete darkness but you see just fine with the UV flashlight? I suppose that would be cool, not sure how useful that would be but interesting anyway.
Well, it'd be almost complete darkness, except for everything that fluoresces, which actually is quite a lot of things. Maybe he can get a job as plainclothes security at fun houses lit by black-light. Everyone else just sees teeth and the random glowing t-shirts and socks, whereas he sees everything else.
Narishma already said it here, but I was referring specifically to machines that used the TMS9918/28/29(A) VDP, often just referred to as "the VDP." So far as I know no system that uses the VDP was able to memory map and dynamically multiplex CPU and VDP access to the 4K or 16K of DRAM connected to it. And, that walled off access to the DRAM was a particular drawback for machines that used the VDP, which is why I pointed it out.
Did you disable the wait states for the extra 32K RAM? I seem to recall that it did an address decode, and if the access was to the 8-bit bus and not to the VDP, it threw in a ton of wait states.
It's not really RGB output, but rather Y, Y - R and Y - B luma/color difference signals -- actually frightfully close to S-video. But I'm pretty sure they had an app note back in the day that showed how to sum those to get RGB almost trivially.
The reason they went with the 9928A (and later 9128A) was to avoid the "rainbow effect" that was is prominent on the 9918A. See, the 9918A didn't flip the chroma carrier field-to-field, which leads to reinforcing chroma errors. That's also why you couldn't use the EXT VIDEO input on the 9918A to mix with arbitrary video sources (say, for a video overlay), but you could use it to daisy-chain VDPs to get more sprites and such.
Actually, it was 32 sprites, with a limit of 4 to a line. It had collision detection but it was rarely useful. It had a single bit to tell you that any sprite hit any other sprite. To figure out what hit what, you'd have to walk the descriptor list and do the actual computation yourself. (Or, in the case of TI Extended BASIC, the interpreter had to do it for you.)
On the TI-99/4A, that meant actually accessing VDP memory, since there wasn't much other RAM in the system. That itself was pretty slow, because it wasn't memory mapped for the CPU. You have to write to the VDP's address register, and then do repeated reads after it fetched the byte. Depending on the display mode, that could be as long as 8us during active display (Graphics II mode -- everybody's favorite "bitmap" mode.). Fortunately, the address pointer auto-incremented, so if you were accessing a contiguous structure like the sprite descriptor list, at least you didn't have to keep reloading the address.
Not that TI Extended BASIC was necessarily able to do that, of course. (Read up on the abomination that was GPL. Not the license, but the interpreted language that much TI software was written in, including TI BASIC.) But if you wrote your own assembly code, you could make that optimization, which is probably how Parsec was able to do its soft-scrolling in the time allotted.
(Actually, VDP RAM isn't memory mapped on any platform that I know of. But other systems have CPU-addressable memory that you could store a shadow copy of data in at least. The paltry 256 bytes on the TI-99/4A, though, are far from enough in many cases.)
Probably the biggest problem is going to be all the old school electrolytic capacitors. I know my TI-99/4A is a bit flaky, and I suspect that's why. The VDP was running at the edge of process technology in those days (5.37MHz!) and it wants nice, clean clocks and nice clean supply rails. The rest of the machine runs a fair bit slower, with possible exception of the 256 byte SRAM that the TMS9900 CPU stores its "registers" in.
Thankfully, those big old electrolytic cans are easy to spot and easy to solder in replacements for.
My own oxymoronic description of Steve Jobs is that he was an empathic sociopath. He was very empathic towards his customers--at least on the front of providing a cohesive, friendly product and product experience and working tirelessly to get there--but rather sociopathic toward the people nearest him. Throw in his famous charisma and tada! Steve Jobs.
The empathy itself is a faux empathy, though, so it perhaps isn't such the contradiction that it seems. I think Steve keenly understood the Paradox of Choice, and had no problem making all the choices for his customers. He lucked out having a great sense of taste coming from his sense of minimalism.
When I hired into a high tech company in 1996, they were still using a home-grown electronic mail system running on a mainframe, using a tn3270 emulator to access it. Most people had transitioned to SMTP mail for most purposes (they quaintly called it "Internet mail"), but there was still an important segment of mail traffic that went over the old system.
The older, proprietary message system did allow mixed case, and most people used it that way. But, there were still a handful of people (mostly in HR) that had been there 20+ years, and still sent all their messages in ALL CAPS. (One person I remember specifically had their tn3270 emulator set to force CAPS mode.)
That proprietary system got retired about 2 years after I hired in. I wasn't sad to see it go.
My point, anyway, is that old habits die hard. Mixed case may have been supported or may not have been, but ALL CAPS was slow to die out in certain corners. Heck, aren't NWS alerts still in ALL CAPS?
In lieu of a car analogy... does anyone else NOT see this as the corporate equivalent of rearranging deck chairs on the Titanic?
I can't remember the last time I considered Yahoo! relevant. Sure, I have an email account with them and I use YIM, but they're not really differentiated in any way. I could lose both and still continue on with GMail and GTalk, for example. (Ok, so YIM has a bigger "smiley" set. Ooh. Big whup.)
Ok... blinking-red-on-green mouseovers, a dynamic <TITLE> tag, and blinking green text in the text. I guess he gets a pass. Although, he'd've gotten extra super old-skool bonus points for a page that said "This page is a searchable index. Enter a search term: __."
I agree. Oddly, there doesn't seem to be a _Restrict in C99, only restrict. Or did I miss it?
Also, he appears to be confused about the roles of the leading underscore. He confuses the ABI convention and the source code convention. The ABI convention of prefixing symbols that have external linkage with an underscore is not specified by the C language, and many systems don't actually do that any more. My Linux box sure doesn't. The new ELF ABI for the DSP family I work with doesn't (but the older COFF ABI does). The source-level convention of reserving identifiers with a leading underscore (followed by a capital letter or another underscore) for the compiler goes back to C89. That's 22 years ago.
The quiz in the article is misleading. That is not the level or style of question that was presented to the school board member. The NAEP test he took was not multiple choice, apparently.
I'm pretty certain we did geometric proofs in 10th grade geometry. (ie. "Prove angle XYZ and ABC are complementary angles.") We also did some basic algebraic proofs. And that was before they added the advanced math track in that school district.
Oh, I think 10 is an abysmal score for exactly the reasons you mentioned. I'm just saying that the gorilla mashing buttons perfectly at random that he was compared to could be reasonably expected to get a score in the range 8.3 to 21.7 with about 95% likelihood.
The thing is that the 10th grade test is likely where the exam switches from "things I can mash on a calculator" that requires just basic algebra skills at best, to more abstract concepts such as geometric properties and proofs, trigonometric identities, more advanced algebraic techniques and so on. This stuff is important if you want to go into certain fields, but not necessary for going into management.
Slashdot Mirror
Well, it did do a lot for you. And the large RAM with flexible descriptor tables meant that in practice, you could avoid doing too many writes over to the VDP most of the time. And, the separate dedicated-RAM architecture does guarantee no cycle stealing, unlike, say, the VIC and VIC-II chips in the Commodore computers, or the need to wait for horiz/vert refresh to avoid "sparkles" like the old CGAs.
Let's face it, all these old computers were an exercise in tradeoffs.
I see the spot/crosshatch pattern on car windows when I wear polarized shades. I don't see Haldinger's brush, though, when I'm wearing no glasses. The pattern on car windows comes from the glass-tempering process.
I just had an image of Nigel Tufnel pointing to his left ear after such a test saying "This one goes to 11 . . . kHz."
Careful with that superpower. You'll put your eye out.
Well, it'd be almost complete darkness, except for everything that fluoresces, which actually is quite a lot of things. Maybe he can get a job as plainclothes security at fun houses lit by black-light. Everyone else just sees teeth and the random glowing t-shirts and socks, whereas he sees everything else.
Narishma already said it here, but I was referring specifically to machines that used the TMS9918/28/29(A) VDP, often just referred to as "the VDP." So far as I know no system that uses the VDP was able to memory map and dynamically multiplex CPU and VDP access to the 4K or 16K of DRAM connected to it. And, that walled off access to the DRAM was a particular drawback for machines that used the VDP, which is why I pointed it out.
Did you disable the wait states for the extra 32K RAM? I seem to recall that it did an address decode, and if the access was to the 8-bit bus and not to the VDP, it threw in a ton of wait states.
It's not really RGB output, but rather Y, Y - R and Y - B luma/color difference signals -- actually frightfully close to S-video. But I'm pretty sure they had an app note back in the day that showed how to sum those to get RGB almost trivially.
The reason they went with the 9928A (and later 9128A) was to avoid the "rainbow effect" that was is prominent on the 9918A. See, the 9918A didn't flip the chroma carrier field-to-field, which leads to reinforcing chroma errors. That's also why you couldn't use the EXT VIDEO input on the 9918A to mix with arbitrary video sources (say, for a video overlay), but you could use it to daisy-chain VDPs to get more sprites and such.
Actually, it was 32 sprites, with a limit of 4 to a line. It had collision detection but it was rarely useful. It had a single bit to tell you that any sprite hit any other sprite. To figure out what hit what, you'd have to walk the descriptor list and do the actual computation yourself. (Or, in the case of TI Extended BASIC, the interpreter had to do it for you.)
On the TI-99/4A, that meant actually accessing VDP memory, since there wasn't much other RAM in the system. That itself was pretty slow, because it wasn't memory mapped for the CPU. You have to write to the VDP's address register, and then do repeated reads after it fetched the byte. Depending on the display mode, that could be as long as 8us during active display (Graphics II mode -- everybody's favorite "bitmap" mode.). Fortunately, the address pointer auto-incremented, so if you were accessing a contiguous structure like the sprite descriptor list, at least you didn't have to keep reloading the address.
Not that TI Extended BASIC was necessarily able to do that, of course. (Read up on the abomination that was GPL. Not the license, but the interpreted language that much TI software was written in, including TI BASIC.) But if you wrote your own assembly code, you could make that optimization, which is probably how Parsec was able to do its soft-scrolling in the time allotted.
(Actually, VDP RAM isn't memory mapped on any platform that I know of. But other systems have CPU-addressable memory that you could store a shadow copy of data in at least. The paltry 256 bytes on the TI-99/4A, though, are far from enough in many cases.)
Probably the biggest problem is going to be all the old school electrolytic capacitors. I know my TI-99/4A is a bit flaky, and I suspect that's why. The VDP was running at the edge of process technology in those days (5.37MHz!) and it wants nice, clean clocks and nice clean supply rails. The rest of the machine runs a fair bit slower, with possible exception of the 256 byte SRAM that the TMS9900 CPU stores its "registers" in.
Thankfully, those big old electrolytic cans are easy to spot and easy to solder in replacements for.
That's a reheat (and slight reworking) of this old piece.
How much longer until text deflation leads to nothing but lines and dots? .... -- -- -- .-.-.-
Fair enough. Good point.
My own oxymoronic description of Steve Jobs is that he was an empathic sociopath. He was very empathic towards his customers--at least on the front of providing a cohesive, friendly product and product experience and working tirelessly to get there--but rather sociopathic toward the people nearest him. Throw in his famous charisma and tada! Steve Jobs.
The empathy itself is a faux empathy, though, so it perhaps isn't such the contradiction that it seems. I think Steve keenly understood the Paradox of Choice, and had no problem making all the choices for his customers. He lucked out having a great sense of taste coming from his sense of minimalism.
When I hired into a high tech company in 1996, they were still using a home-grown electronic mail system running on a mainframe, using a tn3270 emulator to access it. Most people had transitioned to SMTP mail for most purposes (they quaintly called it "Internet mail"), but there was still an important segment of mail traffic that went over the old system.
The older, proprietary message system did allow mixed case, and most people used it that way. But, there were still a handful of people (mostly in HR) that had been there 20+ years, and still sent all their messages in ALL CAPS. (One person I remember specifically had their tn3270 emulator set to force CAPS mode.)
That proprietary system got retired about 2 years after I hired in. I wasn't sad to see it go.
My point, anyway, is that old habits die hard. Mixed case may have been supported or may not have been, but ALL CAPS was slow to die out in certain corners. Heck, aren't NWS alerts still in ALL CAPS?
So it has a chance to survive in spite of its parent's failure.
And some people survived the Titanic in life boats. If Flickr is the only thing relevant about Yahoo!, then spin it off and let Yahoo! die.
In lieu of a car analogy... does anyone else NOT see this as the corporate equivalent of rearranging deck chairs on the Titanic?
I can't remember the last time I considered Yahoo! relevant. Sure, I have an email account with them and I use YIM, but they're not really differentiated in any way. I could lose both and still continue on with GMail and GTalk, for example. (Ok, so YIM has a bigger "smiley" set. Ooh. Big whup.)
Ok... blinking-red-on-green mouseovers, a dynamic <TITLE> tag, and blinking green text in the text. I guess he gets a pass. Although, he'd've gotten extra super old-skool bonus points for a page that said "This page is a searchable index. Enter a search term: __."
(Tongue firmly planted in cheek, of course.)
No Hamster Dance integration?
I agree. Oddly, there doesn't seem to be a _Restrict in C99, only restrict. Or did I miss it?
Also, he appears to be confused about the roles of the leading underscore. He confuses the ABI convention and the source code convention. The ABI convention of prefixing symbols that have external linkage with an underscore is not specified by the C language, and many systems don't actually do that any more. My Linux box sure doesn't. The new ELF ABI for the DSP family I work with doesn't (but the older COFF ABI does). The source-level convention of reserving identifiers with a leading underscore (followed by a capital letter or another underscore) for the compiler goes back to C89. That's 22 years ago.
More like $360 USD.
The quiz in the article is misleading. That is not the level or style of question that was presented to the school board member. The NAEP test he took was not multiple choice, apparently.
I'm pretty certain we did geometric proofs in 10th grade geometry. (ie. "Prove angle XYZ and ABC are complementary angles.") We also did some basic algebraic proofs. And that was before they added the advanced math track in that school district.
Oh, I think 10 is an abysmal score for exactly the reasons you mentioned. I'm just saying that the gorilla mashing buttons perfectly at random that he was compared to could be reasonably expected to get a score in the range 8.3 to 21.7 with about 95% likelihood.
The thing is that the 10th grade test is likely where the exam switches from "things I can mash on a calculator" that requires just basic algebra skills at best, to more abstract concepts such as geometric properties and proofs, trigonometric identities, more advanced algebraic techniques and so on. This stuff is important if you want to go into certain fields, but not necessary for going into management.