Re: Re: MISC personal computers -Reply

[Jaap van Ganswijk <ganswijk@xxxxxxxxx>]

At 19:22 19990215 +0100, M. Simon wrote:
>>>>What clients in this field often want is that there is progress in the
>>>>development process of the processor. When I buy an n Mips processor
>>>>today, can I buy an 2n MHz processor next year to satisfy the growing
>>>>requirements of my own clients and my software etc. (Or when the
>>>>processor turns out to be too slow after my software development
>>>>cycle of several months.)
>>>
>>>The proliferation of processor types are about to put an end to this.
>>
>>What do you mean?
>
>How many different processor types can a manufacturer support?
>
>Motorola already has 100s of processors.
>
>Perhaps they can support 1000 or so different processors.
>Can they support 10,000?

Motorola has much more processors than it can support. Getting
parts has been a big problem the last couple of years, I believe.
One needs to plan to use only types that are going to be popular.
There is also a fatalist attitude among the design staff and I haven't
seen any beautiful processors from Motorola since the 6811.
I think the 68000 and PowerPC are very ugly. The 6812 was
aimed at assembler programmers, so outdated at birth. Their
own RISC processor, the 88000, was withdrawn quite quickly
after release. The other designers don't seem to have read H&P...
The 68020 was revived by the marketing department as 'variable
instruction size RISC' under the name Coldfire. It was strangely
enough crippled by a maximum instruction size. I have never seen
the need for the 6816 family etc. Not nice.
I wouldn't buy Motorola stock based on the semi division...

>>>FPGAs are the future.
>>>
>>>And a low risk way of doing MISC.
>>
>>Do you mean including a small fast processor like MISC into the FPGA?
>
>Yep.
>
>>But how about the costs, the chip size, the heat dissipation, the
>>unnecessary pin amounts, the design costs etc.?
>>This can never beat the sub $1 Z8's etc...
>
>FPGAs are coming down in price rapidly as volumes go up.
>
>Where they really shine is being able to integrate peripherals
>on the chip.

Problem is that pin-count and surface size determine real mass market
costs. And that battery life-time is very important.

>I have a Z80 board with lots of I/O that could be reduced to a single FPGA
>with external RAM and EPROM. Same price. 10X the processing speed.
>Smaller board. Lower power.

Why not integrate the RAM and ROM? RAM is only 128 to 256 bytes
for most applications. ROM size is much more essential. I once had to do
a project in the 4Kbyte of a 6811. Was really a shuffle of which functions
to include in the test-versions, because during testing a lot of extra code is
often added temporarily.
These things make software engineers cost a lot of money.

>>PS. Why aren't we discussing this on the list?
>
>Because I tried posting to the list a while back and my posts never took.

Seems like the default is 'answer to the poster' and not 'to the list'.
It requires special attention in most email readers to get the thing right.
Can't this be changed mailing list manager?

>Feel free to post this stuff if you are interested.

Okay!


Groeten/Greetings,
Jaap

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