Decimal V Binary??

From: Paul Koning <pkoning_at_equallogic.com>
Date: Thu Sep 23 10:56:41 2004

>>>>> "Doc" == Doc Shipley <doc_at_mdrconsult.com> writes:

 Doc> Ed Kelleher wrote:
>> DEC PDP11/23 CPU has sockets for 2 extra chips (40 pin DIPS).
>>
>> One is hardware floating point. This is fairly common.
>>
>> The other for a CIS - Commercial Instruction Set with full set of
>> decimal instructions as you list.

 Doc> The dual-height 11/03 processor allows a CIS as well. I have a
 Doc> couple that have that chip. As far as I can determine, both
 Doc> those machines were used to sort, analyse, and archive incoming
 Doc> raw data.

 Doc> Honestly, though, I don't think I've ever run a job on the /03
 Doc> that touched the CIS.

I would assume that Cobol and (possibly) RPG would have an option to
use CIS if available, but no other language is likely to do so.

There was a DEC internal prototype of an 11/70 with CIS added; it was
called 11/74 I believe (not to be confused with the SMP machine also
referred to as 11/74 that the RSX development team used). Apparently
it was canceled shortly before it was ready to ship. Nasty rumors
claimed that this was because it was outperforming the 11/780 in every
way; I don't know how valid that might be.

     paul
Received on Thu Sep 23 2004 - 10:56:41 BST