What was wrong with the 464?

[sigh]

Sinclair QL, Machintosh128...
Really... CPC480 would have changed a real lot of things on the paper.
A CPC6160 as well.

The Sinclair QL - I liked what they were trying to do with this.

Useborne Guide To Expanding Your Micro which was published in 1984 has this:


Apple IIC had 128k
Apple IIE 64K Standard Expandable to 128k
Memotech MTX-500 32k Standard Expandable to 512k


A Sinclair QL could be upgraded to 640k


Later Apple IIE machines came with 128k as standard, not sure when this happened though.

...that's a lot more than I had thought!

[MacDeath]

Most of those machines were quite expensive though...

That's why I think the 80K approach with empty slots for extras could have been a good compromise.




If i remember some CPC boards series would have some empty chip slots. What was this for ?

[ivarf]

The Sinclair QL - I liked what they were trying to do with this.

But what they achived wasn't that impressive. Even the Amstrad CPC was faster than the QL. Basic benchmarks, but still. What were the latest revision of the QL and how long had people to wait before they finally arrived? Many months...


But I am off, I do not what they were trying to achive with the QL

[MacDeath]

QL was also plagged by those shitty microdrive tape based Mass data storage... seriously ?

With an internal 5"1/4 disk drive "à la CPC6128/664" it would have been a more serious machine.


128K is a bit low on RAM for a 68000 machine as well, but it could easily be extended I guess.

From what I remember, the video modes weren't really good.

Two video modes were available, 256×256 pixels with 8 RGB colours and per-pixel flashing, or 512×256 pixels with four colours (black, red, green and white). Both screen modes used a 32 kB

oh, is that a teletext palette ?

Wow, even the speccy actually had a better palette or Am I Wrong ?
Even PC1512 as well...


Video modes manage to be both heavy and inefficient as graphic oriented applications.
Was Sinclair colour blind ?

what about sounds ? don't tell me it is jsut a beeper ?


QL could have been great with at least a real Disk Drive, an AY soundchip and an EGA 64 colour palette to choose inks from.
otherwise it was just a pre-1984 8bit computer fit with a 16bit CPU.

CPC was more well rounded despite being 8bit, Atari ST did it right in 16bits as well.

[gerald]

If i remember some CPC boards series would have some empty chip slots. What was this for ?

On pre-asic board, you can either fit 64k*1 bit or 64k*4bit devices. But i've never seen 64k*4bit devices in these.

[TFM]

So does that mean it doesn't have 72Kb, or it does, but it needs a custom program to access the 8Kb. I know someone had to do this to access the 8Kb in a Multiface 2, it was interesting, though obviously more involved compared to punching out some OUT statements.

They just soldered the additional 8 KB on back of another chip. But you can not access it. It's a 64 KB machine. I opened one of the CPC472 couple years ago. The 8 KB chip is there but not connected.

[AMSDOS]

Most of those machines were quite expensive though...

Don't know how much they went for, but in 1984 other computer manufacturers had RAM Packs / RAM Chips or RAM Cartridges available and other computers like the Dragon 32 or a Sinclair Spectrum with 16Kb had the option of returning the computer to the Manufacturer for upgrade. I guess if Amstrad gave the option of a 16Kb RAM Pack it would of been a good marketing strategy.


Having said all that, are Amstrad's fussy with regard to what size the RAM is. I guess if the machine works in 16Kb combinations that would work. I had a 386 and put a 4Mb RAM Chip in that along with the other 1Mb Chips which didn't work, I found out afterwards this was a limitation of the 386 and it needed RAM pairs for it to work.

[chinnyhill10]

Don't know how much they went for, but in 1984 other computer manufacturers had RAM Packs / RAM Chips or RAM Cartridges available and other computers like the Dragon 32 or a Sinclair Spectrum with 16Kb had the option of returning the computer to the Manufacturer for upgrade.

Dragon and Sinclair both went bust. Tells me all I need to know. Last thing you want is for people to be sending machines back to be upgraded when your machines are made in a state of the art factory in South Korea, compared to Sinclair who made their machines in a factory in Dundee not known for its build quality!


Amstrad had NO interest in selling a RAM upgrade but didn't preclude external suppliers such as DK'tronics supplying them.

[TotO]

Amstrad had NO interest in selling a RAM upgrade but didn't preclude external suppliers such as DK'tronics supplying them.

The 464 "Expansion Port" is called Floppy Disc Port, because it's a downgraded version that allow to save some electronic parts. Its only usage was to add the DDI-1 that include the ROM7 (triple nand gate decoding) for AMSDOS. When added, the EXT signal is grounded to know if the computer is fully extended. No more, no less.

So, yes, Amstrad had never planned to add memory to this computer and never planed to release the 6128 too.
They have just planed to release the 664, embedding this expansion for peoples with more money. (and a color monitor)

About the DK'Tronics RAM expansions, there was released after the 6128 was out to allow new softwares to be compatible.
So, Amstrad was able to do the same, but... Why doing that if an other company do it for you?

The 464/664 range of computer are not able to properly handle external RAM w/o forcing the /MREQ signal with a transistor.
It's why, most of the existing RAM expansion for 464 are internal and plugged over the Gate Array socket, to avoid this dirty hack.

[Gryzor]

@chinnyhill10 is spot on. Amstrad wanted to mass-produce and forget. Hence the higher quality/lower return rates, too. The option to send back to the manufacturer was antiquated even then as an idea, and we all know how behind schedule Sinclair's manufacturing constantly fell...

[TotO]

I have found a way to mold new keyboards... 
The Keyboard Waffle Iron by Chris Dimino, Designer — Kickstarter

[AMSDOS]

128K is a bit low on RAM for a 68000 machine as well, but it could easily be extended I guess.

[ot]
The trouble there was an computer like an Apple Lisa which had 1Mb as standard went for nearly $10,000US in 1983 and lacked Colour. Though according to Wikipedia the Apple Lisa had a number of differences from the Mac class system with some of the features such as the Protective Memory from the earlier Lisa being implemented into Mac Based Systems.
[/ot]

[sigh]

I wonder if there would of been a cheaper way of creating an 128kb machine by having having 4 32kb chips or even 8 16kb chips on the board.

[TotO]

128K is a bit low on RAM for a 68000 machine as well, but it could easily be extended I guess.

Megadrive and Neogeo used 64K of RAM for the 68000. When you use ROM, it's not a big problem.

I wonder if there would of been a cheaper way of creating an 128kb machine by having having 4 32kb chips or even 8 16kb chips on the board.

As 32KB IC doesn't exist when the 464 was released, it's a false question.
In all cases, 32K IC had been more expensive than two 16K IC. (only saving space on the design had been a good reason to use them)

[sigh]

Megadrive and Neogeo used 64K of RAM for the 68000. When you use ROM, it's not a big problem.
As 32KB IC doesn't exist when the 464 was released, it's a false question.
In all cases, 32K IC had been more expensive than two 16K IC. (only saving space on the design had been a good reason to use them)

But didn't the MSX have 32KB ram chips? They were out before the CPC in 1983.

[Bryce]

But didn't the MSX have 32KB ram chips? They were out before the CPC in 1983.

Using different capacity chips wouldn't have had any real effect on the price. The price per Kilobyte was pretty much the same, the only real saving would be on PCB space.

Bryce.

[TotO]

But didn't the MSX have 32KB ram chips? They were out before the CPC in 1983.

Is 32K x4bit or 32K x8bit chip?

[sigh]

Is 32K x4bit or 32K x8bit chip?

I have no idea. Is the x4bit version cheaper?

Using different capacity chips wouldn't have had any real effect on the price. The price per Kilobyte was pretty much the same, the only real saving would be on PCB space.

Bryce.

I see.


Out of interest, if they were to have separate ram chips on the board, would this effect the programming of software? For instance, would separate ram chips have given the coders more control on how the ram is used?

[TotO]

I have no idea. Is the x4bit version cheaper?

That allow to make smaller IC, because less pins.
32K x4bit is 16KB memory.

[Bryce]

Out of interest, if they were to have separate ram chips on the board, would this effect the programming of software? For instance, would separate ram chips have given the coders more control on how the ram is used?

No, it doesn't change anything. The address decoding is what defines the limits.

Bryce.