View Full Version : Mp/m

May 3rd, 2010, 03:31 AM
I noticed that this Genre is for "CP/M and MP/M" and so I tried putting MP/M into the search and the forum has come up with no hits. Maybe there are some MP/M threads hidden away, but in order to shift the balance for this Genre from CP/M to MP/M, this is a little announcement that we now have MP/M working on the propeller emulation. http://smarthome.viviti.com/build and click on the MP/M link for some text and click on the Propeller link for the hardware. At present the hardware has two serial ports, one local vga, one keyboard and one small 20x4 LCD. User0 is the first serial port. User1 is the local keyboard and vga (those can be swapped) and user2 is the second serial port. All users can talk to the 20x4 LCD for debugging purposes, and all users can talk to each other.

MP/M runs from a CP/M prompt.

My first computer was a CP/M computer and it came with a book that also was written for MP/M. I always wanted MP/M as it could do more than CP/M. Now, 27 years later the wish has come true!

Has anyone got a real MP/M computer? I'd be interested to see what the hardware looks like, particularly the bank switching.

May 3rd, 2010, 06:59 AM
This looks like a really fun project to build a and play with. Total cost around $50.00!

May 3rd, 2010, 07:33 AM
I have an Altos 5-5AD that has MP/M on it but no pictures.

May 3rd, 2010, 08:22 AM
Has anyone got a real MP/M computer? I'd be interested to see what the hardware looks like, particularly the bank switching.
I've got an Altos 580. It ran MP/M until the hard disk died.

You can find schematics for the Altos on Bitsavers (http://bitsavers.org/) or one of it's mirrors.
Download the file Altos580-10_and_Series_5_Nov82.pdf
The schematics are near the end of that file.


May 3rd, 2010, 09:13 AM
I've done a couple of MP/M ports many years ago and still have an unused MP/M OEM kit, complete with price list.

MP?M, while it may have worked for some specific applications, in general, was a failure. Many CP/M programs refused to run successfully; there was no real security between users and the 8-bit hardware as well as the flat single-directory filesystem was ill-equipped for it. The 16-bit systems (68K, x86) has some sort of hardware support for dynamic relocation and in general, worked much better. CP/M 3 (plus) was more successful as a product, even though it employed large sections of MP/M.

There were other more promising multi-user efforts, such as using 1 CPU for each user, but for system requests, more or less completely isolated. Getting multi-user (multi-tasking) right in a useful way is more difficult than most people really think.

May 3rd, 2010, 03:49 PM
The hardware is flexible too.
1) CP/M
2) CP/M running MP/M
3) and now, a NASCOM
4) and a TRS80

I've attached a screenshot of Pacman and Space Invaders on the Nascom here http://www.smarthome.viviti.com/propeller

May 4th, 2010, 01:00 AM
I started a friend on the path to being a computer security professional by dinking around with his sessions and programs under MP/M on a Northstar Horizon in high school. ;)
I wrote a session emulationprogram that would occasionally report obscure errors or otherwise act odd (it changed frequently.)
I was nice enough to make it actually save his work before scaring him, though (reporting write errors, etc.)

What he learned while dealing with my poor manners got him a job, later.

Our system had 64K, so no bank-switching was used.