difference between LSI-11 CPU's M7264 and M7270 - test-drb@ccmp.vtda.org

27 Sep 2005

...
  -----Original Message-----
 From: cctalk-bounces at classiccmp.org 
 [mailto:cctalk-bounces at classiccmp.org] On Behalf Of Allison
 Sent: dinsdag 27 september 2005 16:18
 To: cctalk at classiccmp.org
 Subject: Re: (no subject)

Subject: (no subject)
   From: Frank Arnold <fm.arnold at gmx.net>
   Date: Tue, 27 Sep 2005 15:24:06 +0100
     To: cctalk at classiccmp.org

>
>Message: 28
>Date: Mon, 26 Sep 2005 13:42:48 +0200
>From: "Gooijen, Henk" <GOOI at oce.nl>
>Subject: RE: difference between LSI-11 CPU's M7264 and M7270
>
>> -----Original Message-----
>> On Sep 26 2005,  8:40, Gooijen, Henk wrote:
>> 
>> 
>> <-- M7270 -LSI11/2--> <--- M8044 MSV11----> 
>> <------ empty ------> <--- M7940 DLV11---->
>> <------ empty ------> <------ empty ------>
>> <------ empty ------> <------ empty ------> 

Henk, there is no bootstrap in this system....

The FieldGuide says that a few lines are used for something 
else, but I expect (hope) that the M7270 and the M7264 usage
of all connections is identical. 
No, I think only the LSI11 suplies refresh to the bus, 
LSI11/02 does not.
They use some of the sspare lines for that, that much later got
used for Adressbits 19-21 once Q-bus got Q22  
 Correct on refresh, the 7270 does not provide it (not needed 
 for 8044 memory).
 However, the unused microcode lines are not used for refresh. 
  Those are use for special (unimplmented) microcode. 

  Regarding
the M8018 WCS option: is this "just" a chip, like 
FIS or the big CIS one? 
Those are LSI11/23 options...  
 The M8018 KUV11-AA is for the M7264 (LSI-11, KD11-f), I have 
 also tested it with M7270 (LSI11/2)(sort of a hack).

 There was a microcode WCS option for the 11/23.  It is also a 
 board. I don't think it was ever sold.  There was a FPU option
 M8188 (FPF11) a quad width board for the 11/23 that was sold.

 Unfortunately I dont have this (still hunting),
but yes, it
is a board. It takes only the power from the Q-bus and connects
with a flatcable to the microm socket on the LSI-11 module.
I also heard the fact that this works (or was DEC-supported) only
on the quad LSI11, but can't see a good reason for this, as the
chipset is identical. It even has the empty socket to connect the
WCS-option.  Maybe the engineering drawings will tell more.  
 It was design specific for the M7264-YC though it seemed to 
 work with any of the M7264 or M7270 modules (microcode 
 address specific caveat).
 The DEC supported config was on the M7264-YC. The difference 
 is that each microm socket has a unique microcode address and 
 is diagnostic specific.

 Allison 
Thanks, Frank and Allison.
I guess, now is a good moment to start reading the LSI-11 handbook
and to look out for a bootstrap kind of module !  Is there a specific
module to look for, or are there several possibilities?  Remember,
this system only has 4 slots (almost 2 occupied), and I want to add
at least modules to get some parallel I/O (TTL) lines, and to boot
the system from (Pete Collum's RXV11) ...

The idea that I have for this system is the following.
I want to use a small 486 system as terminal and mass storage.
The parallel I/O will interface to a filter-based RTTY demodulator.
Software (to be written) will turn this setup to a telex reception
station (transmitting RTTY will follow!)  I know that many programs
already exist for this (not on PDP-11), but I want to learn MACRO-11
and learning a language goes best if you have an application idea.
I expect it will not be difficult, after I learned the way MACRO-11
wants its assembly text, because it looks quite like M68000 mnemonics.
That will probably cause some pitfalls, but I must look up all the
PDP-11 mnemonics in the beginning anyway.

Fun job for this winter!

  73,
- Henk, PA8PDP. 