Path: utzoo!utgpu!news-server.csri.toronto.edu!mailrus!tut.cis.ohio-state.edu!zaphod.mps.ohio-state.edu!usc!elroy.jpl.nasa.gov!decwrl!jumbo!ehs
From: ehs@jumbo.dec.com (Ed Satterthwaite)
Newsgroups: comp.sys.m68k
Subject: Re: Signetics 68070
Message-ID: <14735@jumbo.dec.com>
Date: 23 Mar 90 22:14:38 GMT
References: <11857@etana.tut.fi> <1990Mar20.171614.12694@chaos.cs.brandeis.edu>
Organization: DEC Systems Research Center, Palo Alto
Lines: 49

(My apologies if this one has already been done to death -- we lost our
netnews feed for a few days this week.)

In article <1990Mar20.171614.12694@chaos.cs.brandeis.edu>, topgun@chaos.cs.brandeis.edu (Chandra Bajpai) writes:
> 
> Does anybody have any information on the New 68070 Signetics microprocessor?
... summary of features
> Is this chip available?  What is Signetics asking for '070 in volumes?

It's actually not all that new; I have a User Manual dated 1988 and a data
sheet (Product Specification) dated May 1989.  The SCC68070 is in the
current Signetics price book with clock speeds of 10, 12.5 and 15 MHz.
Prices in quantity 1000 are $20 or a bit less depending on speed grade;
quantity 1 prices about $10 higher.

Philips (Signetics' parent company) is making several variations on the
same theme in its 90c1xx family.  The 93c110 has on-chip ROM, RAM, and
EEPROM and lots of configurable port pins but no DMA or MMU.

If this sort of part fits your application, look at the Motorola 68302 as
well.  It's based on a 16.7 MHz 68hc000 core with

  on-chip dual-ported RAM (1152 bytes, partially dedicated to control blocks)
  3 full-duplex serial communications channels configurable for most popular
      protocols and supported by 6 internal DMA channels
  optional multiplexing of serial outputs to meet ISDN requirements
  1 external DMA channel
  integrated interrupt controller
  2 parallel i/o ports (some pin functions shared)
  3 timers
  4 programmable chip-select/wait-state generators
  DRAM refresh controller (later revisions only).

This part is definitely real -- one is running the prototype version of my
current project.  Last I checked, the PGA version was ~$45 in quantity
one; there are also quad flatpack versions with pricing comparable to the
68070.  Compared to the latter, the 68302 provides better support for
serial line interfaces and subsumes more of the system glue logic.  On the
other hand, there is only a single external DMA channel and it's less
flexible than the 68070's.  There is also no integrated MMU, if that matters
for some reason.

The 68302 is pretty clearly aimed at the telecom market, especially ISDN.
I've heard that the 68070 was originally done as a high-end controller for
consumer electronics (CD players and the like).   To go further upscale,
there's also the 68332 to consider.

Ed Satterthwaite
ehs@src.DEC.COM  or {...}!decwrl!ehs