[HECnet] Intro and New User Questions

[Mark Matlock]

Dave,
  I totally agree with you! A DECnet connected data acquisition system is also a dream of mine as well. Currently my MINC runs either a 11/23 CPU with enhanced BDV-11 EPROMs with code from an 11/23+ so it will boot DU devices or a 11/73 that boots the DU directly. The disk is a SCSI2SD that can run RT-11 on 4 RD54s or RSX11M via a UC07. The microSD has a cable to the front panel that accepts regular SDCARDS so operating system changes are a card card change and reboot.

  I’m trying to get some insight on the MINC module’s CSRs which are very close to ADV11, AAV11, KWV11-C (the interupt enable bit may be different), and DRV11s. RT-11 has software to allow BASIC to acquire the data, but I’d rather use Macro-11 for better speed and flexibility.

    On DECnet over serial lines, as Johnny said it actually works quite well. I once had a PDP-11/24 and used the second serial port on the CPU board as a DECnet line. It connected me to our corporate headquarters about 250 miles away.

    I also worked on a system where we had disk-less 11/23s download RSX11S over synchronous DUV11s and use DECnet for the realtime transmission of commodity trading info. It was a star network with 10 RSX11S systems feed by two 11/44s which consumed and distributed data from 8 commodity exchanges to around 200 brokers on VT100s hanging off DZV11s on the 23s.

   Back to the MINC, its backplane is 18 bit so 256KB is all you can have, but I’ve thought about cutting the BDA18 line which is used for another purpose by the ADV11 and then wiring the top 4 address lines at the CPU side of the bus. The MINC devices should only respond to the I/O page signals


Best,
Mark

> On Dec 21, 2017, at 12:06 PM, Dave McGuire <mcguire at neurotica.com> wrote:
> 
>> On 12/21/2017 12:03 AM, Mark Matlock wrote:
>>    Interestingly the documentation also said there was a version of RSX11S with DECnet for the MINC-11. Building RSX11S with DECnet is something I did many years ago for a p[roject at work and could probably redo, but the Macro sources to talk to the MINC-11 A/D, D/A, Programable Clock and Digital I/O modules would be nice to have if anyone ever saw such a thing.
> 
>  The notion of a DECnet-connected, PDP-11-based remote data acquisition
> system is something that I find quite...well, honestly...arousing.
> 
>               -Dave
> 
> -- 
> Dave McGuire, AK4HZ
> New Kensington, PA