Extremely CISC instructions- C compilers.

Todd Goodman tsg at bonedaddy.net
Wed Aug 25 13:58:02 CDT 2021

On 8/25/2021 1:58 PM, ben via cctalk wrote:
> On 2021-08-25 10:27 a.m., Todd Goodman via cctalk wrote:
>> On 8/25/2021 11:49 AM, ben via cctalk wrote:
>>> [..SNIP..]
>>> C uses cheap tricks for speed. 8 bit bytes, 32 bit integers, taken 
>>> from B. I have 21 bit CPU, with 3 7 bit bytes/word. Algol would have 
>>> a PACK/UPACK function, and be fairly portable. C on the other hand a 
>>> mess.
>>> Ok. I don't have 21 bit cpu, but I have this spare FPGA card ...
>> Nope, the standard doesn't specify those bit sizes.
>> Back in the 80s I was using the BBN C Machine with 10-bit bytes and 
>> happily building from source I picked up on the newsgroups with 
>> little issue
> What is the BBN C Machine?

P.110 of https://walden-family.com/bbn/bbn-print2.pdf has some slight 

It was advertised by Bolt, Beranek and Newman as the first computer to 
be designed around the C language.

It had 10-bit bytes and 20-bit words.

At the time I was working there it was used to run all the Network 
Monitoring utilities to manage their commercial networks as well as Ingres.

It's amazing how much was running in 2MB and two "walking 
washing-machine" multiplatter disk pack drives (CDC if I remember right, 
but could be wrong).

Unfortunately all my marketing and engineering materials from my time at 
BBN Communications are gone now.

One of the most memorable moments there was when the Morris worm was 
discovered and someone was sprinting down the hallway and yelling to 
shut down the gateway between the ARPAnet and MILnet

That was also the place where support was having a hard time determining 
why an IMP kept shutting down around the same time every night.  So the 
support guy working the problem decided to set up a video camera at the 
customer site to record the front panel lights to see if he could figure 
out what happened right before it went down.

The camera caught the cleaning crew coming in and unplugging the IMP so 
they could plug in their vacuum

More information about the cctech mailing list