PDP-11 Memory

Bill Gunshannon bill.gunshannon at hotmail.com
Sat Jan 12 16:03:25 CST 2019


On 1/12/19 4:30 PM, allison via cctalk wrote:
> On 01/12/2019 04:14 PM, Bill Gunshannon via cctalk wrote:
>> On 1/12/19 2:25 PM, allison via cctalk wrote:
>>> On 01/12/2019 12:29 PM, Pete Turnbull via cctalk wrote:
>>>> On 12/01/2019 01:24, Zane Healy via cctalk wrote:
>>>>
>>>>> I’m pretty sure you could get the /23+, /53, /73, /83, and /93 in
>>>>> either a BA23 or a BA123.  I have an actual badged BA23 pedestal for
>>>>> my /23+.
>>>> I'm fairly certain all microPDP-11/23+ systems were only sold in BA23
>>>> boxes, and I think microPDP-11/73 and the later, cheaper, cut-down
>>>> 11/53 were as well.  But almost all the 11/83 systems I've ever seen
>>>> were in BA123 boxes, though they did sell some in BA23 pedestals -
>>>> I've got one.
>>>>
>>> Pete,
>>>
>>> Your right the 11/23+ showed up on a lot of boxes but not the BA123
>>> though it would fit.
>> My 11/23+ is in a box labeled PDP-11/23PLUS on the front with
>> three toggle switches.  :-)  It has a 9276-A backplane labeled
>> OPTION 11/23B. It is a 9 slot, Q22 A-B-C-D .  That's the home
>> for my next system which will (hopefully) have 2 meg of memory,
>> a DEQNA and an Andromeda Card for a small hard disk and 8" floppy.
> BA11 box with one of the usual two common backplanes or standard BA23.
> 
> Problem with DEQNA is what OS?  RT11 does nothing with it.  RSX-11
> I don't have a recent enough version so its often unused/

My only problem is I have 3 DEQNA and 1 DELQA.  I thought I read
somewhere recently that the DEQNA was the better of the two.

As for software, what about the Kent TCPIP package?  Will that
not work with the DEQNA?  I thought the two Ethernet controllers
for QBUS were functionally the same.

And, while we are at it, if I type BOOT XH does it look for a
MOP Server?
> 
>> I also plan on another small 11/23 with 128KW of memory and an
>> 18 bit backplane so I can use the RX02 emulator.  And, probably
>> an Andromeda in there, too
>>
>>
>> To bring my part of this discussion to an end, I now have a BA23
>> MicroPDP box with an 11/73 CPU, 4 meg of memory, DHV11 for eight
>> serial lines (probably only use one to talk to a TU58 emulator
>> but the DHV11 was just sitting there looking lonely) a DEQNA
>> and a CMD SCSI Controller set for 6 disks and one tape.  Only
>> thing it lacks at this point is software.
> The TU58 like a responsive IO a DLV11J is a better choice for console and DD
> and works best if first card after the memory (early in the interrupt
> grant chain).

My 11/73 only has a console, thus the need for the DHV11 but really
only one port. (Although I may try putting multiple serial ports in
all the boxes and doing some "networking" over them.  :-)


> The simulators are faster than tu58 so it makes for fewer retries.
> I use DHV11 for terminal and modem lines (slower stuff).
>> On to my next project.
>>
>> Thanks for all the help.  I had forgotten just how much fun
>> real computers were compared to PC's and MAC's.
> Yes they are.  Their performance without all the gui gunk is often a
> suprize
> to many that have not worked with them.


More surprising than most would accept.  It's not a PDP-11 but
I have a 6809 that was sold as a toy for running games that I have
had 4 remote login sessions and a web server running on.  And
that was with networked disks and all remote access over a 115K
serial line on a bitbanger port!!  I would love to see a version
of that OS on the PDP-11.

bill




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