Ben wrote:
What have you sell, that can be shipped and in *small
packages*?
Let me know now, and I can plan to scrape up cash. What I allways
wanted was a Heath 11, or something that has a OS, 32KB of memory
a PDP 11 cpu and working media bigger than mini-floppy size.
I would suggest that you aim a bit higher at a BA23 box since they
are probably just as available as a PDP-11/03 as far as the backplane
is concerned. MegaByte memory should also be available, so the
minimum CPU would be a PDP-11/23. V05.00 of RT-11 supports
the use of the full 4 MegaBytes of the memory and is available.
Well I need real hardware first,how ever 18 bit adressing is ample
for me, providing I have mass media that will last a few more years.
I know nothing about what software or hardware is for the PDP 11
since it was never marketed as a personal product.
The smallest Qbus backplane is one that fits into a VT100 which is
then called a VT103. This backplane is 4 dual slots and just barely
manages. There is also a 4 quad slot version which is likely no more
expensive these days if you can find one - most likely free from an
individual who has graduated to a BA23 box.
There are also independent backplanes with power supply and
4 quad slots, but these are probably harder to find now than a BA23
box and probably only half the size and weight of a BA23.
Since you are
mostly a hardware person (if you want a Heath 11),
what do you actually do with a computer after you have it running?
I ask that since I am a software person. There seems to be an endless
supply of software challenges once the hardware is working.
Well I would like to get a OS and assember/linker/editor as
basic software, but I have no idea cost or legal issues of said items.
PDP 8 software I find on the web, PDP 11 stuff I don't think so.
There are a number of sites which offer PDP-11 distributions.
The site that I used for RT-11 was:
http://www.classiccmp.org/PDP-11/RT-11/dists/
which offers V04.00, V05.03 and ALL (well probably most) of
the binary RT-11 versions up to V05.03 of RT-11. If you want
to learn about RT-11, then the simple way is to use an emulator
running on a PC. Ersatz-11 (which I use most of the time) is free
to hobby users and SIMH is free to everyone as far as I understand,
although that may not be the case. But with Ersatz-11 being much
less than the cost of real DEC hardware when DEC was selling it,
any commercial user will run under Ersatz-11 since it is about ten
times the speed of SIMH which is written in C.
If you need help in running RT-11 after you download an RT-11
distribution, please ask.
Also, which
operating system? In RT-11, the DY.SYS device driver
works very well. BUT the DYX.SYS device driver supports ONLY
an 18 bit address, so the user buffer MUST be below 1/4 MegaByte
in the extended memory for the DEC release. Since all of the DEC
utility programs avoid the use of extended memory, a user buffer above
1/4 MegaByte is a problem only if VBGEXE is being used with a DEC
utility program.
I am single user here,small is better.
Not after your programs become large enough. The maximum program
under RT-11 using VBGEXE is 64 KBytes. Under the SJ unmapped
monitor, programs must be much smaller.
RT-11 distributions are complete with editor, assembler and linker. There
are many utility programs to copy files. Languages such as C and FORTRAN
are available as well. These are called layered products.
The manuals for RT-11 are available at bitsavers. The hardcopy is THREE
feet of manuals in binders. All of the PDF files are available in 21
files of a
total of 12.5 MBytes.
It is usually the data that becomes too large. I have a program that sieves
for prime numbers. Under Ersatz-11, the program has direct access to the
PC memory of over 1 GigaByte and more memory would be better. The
actual code is very small, but when sieving for prime numbers, a larger
work space helps. I should probably switch to a program directly on the
PC, but I enjoy working in RT-11. I am in the midst of a slow (more than
a year) move to Windows XP on an Intel Q9500 quad 2.83 GHz CPU
which runs RT-11 about 100 times as fast as a PDP-11/93 for the CPU
and about 200 times as fast as a SCSI or ESDI hard disk drive using a
SATA 300 hard drive of 1 TB. That provides a lot of storage as compared
to a 600 MB Maxstore or Hitachi ESDI hard drive which is what I run
on the PDP-11/83 out of a BA123 box.
Sincerely yours,
Jerome Fine
