t11 price

[vol.litwr]

I've just browsed the old thread http://www.vcfed.org/forum/showthread.php?24373-Looking-for-a-datasheet-DEC-T11-Cpu. It contains the next information.

The DCT11 ["T11" as we call it] is a great chip for it's time. If it had been executed in CMOS it would have taken over the industry, and been competitive with the Z80.

As you note, the 68K line borrowed a lot from the PDP-11. In fact, as I understand it, NATIONAL actually implemented a PDP-11 clone, which DEC immediately went into litigation over and stopped. I suspect, Motorola took notice, and changed it's designs just enough to keep from becoming embroiled in the same kind of issue themselves.

It is a mystery for me why was this chip used so rarely? It looks better than z80. It has more powerful instructions, higher frequency, better software, ...
What is known about prices in 80s? It is not easy to find this information today, especially for T11. Was T11 available in Europe?
It is also curious what was the price of RT-11SJ at the first half of 80s?
Thanks.

 

[krebizfan]

I thought the T11 was used a great deal; may well have been DEC's best selling CPU. The major problem was it wasn't released until 1981. The Z-80 had been in service for a few years by then. http://simh.trailing-edge.com/semi/t11.html lists a price of $10.

Sold in Europe? I believe so.

In 1977, RT-11 was under $100.

 

[commodorejohn]

I think there's also the factor that it's a 16-bit architecture, in an age of 8-bit systems. Granted, the T11 has an 8-bit bus mode, so it's a shade better than, say, the TI-99 series, where the fact that the TMS-9900 can't even do byte transfers means that every single access to main memory is bogged down, but even though you could hypothetically optimize somewhat for an 8-bit T11 system, there's still the problem that PDP-11 instructions all come in multiples of a word. Of course, you could do the sensible thing and put the 16-bit CPU in a 16-bit system, but then you're looking at (at least somewhat of) an increased cost...