20 Mar
2017
20 Mar
'17
9:20 p.m.
I just wanted to share a little project I've been working on, it's an
adaptation of Lee Davison's EhBASIC to become a timeshared multiuser BASIC.
There's still a bit more to do, but here's a video of it in operation:
https://youtu.be/SAJpHiBPMcQ
In that video, it's only running 3 sessions (I had no convenient 4th
terminal) but it's capable of running 4. It is a very very simple
preemptive multitasking 'kernel' providing I/O services and performing
periodic context switches for the instances of the interpreter. It only
runs a fixed number of processes, and all the process memory is statically
allocated. EhBASIC lends itself well to this, the code is position
independent by design, and the memory range is passed in. Everything is
dereferenced relative to the 'start of memory' pointer. This means no need
for an MMU or relocation.
I'm hoping to set this up at VCF MW in September, running 4 terminals.
More info on the hardware I'm using is available here:
https://hackaday.io/project/6150-beckman-du600-reverse-engineering
Pictures:
https://www.dropbox.com/sh/uw6cjqigk2sdwdy/AAAwP55aelyzrYeP1HVUDdMqa?dl=0
And another software project I'm working on as well (a ROM monitor program):
https://github.com/jzatarski/Joe-Mon
20 Mar
20 Mar
10:10 p.m.
Nice!
On Mar 20, 2017, at 2:20 PM, Joseph Zatarski via
cctalk <cctalk at classiccmp.org> wrote:
I just wanted to share a little project I've been working on, it's an
adaptation of Lee Davison's EhBASIC to become a timeshared multiuser BASIC.
There's still a bit more to do, but here's a video of it in operation:
https://youtu.be/SAJpHiBPMcQ
In that video, it's only running 3 sessions (I had no convenient 4th
terminal) but it's capable of running 4. It is a very very simple
preemptive multitasking 'kernel' providing I/O services and performing
periodic context switches for the instances of the interpreter. It only
runs a fixed number of processes, and all the process memory is statically
allocated. EhBASIC lends itself well to this, the code is position
independent by design, and the memory range is passed in. Everything is
dereferenced relative to the 'start of memory' pointer. This means no need
for an MMU or relocation.
I'm hoping to set this up at VCF MW in September, running 4 terminals.
More info on the hardware I'm using is available here:
https://hackaday.io/project/6150-beckman-du600-reverse-engineering
Pictures:
https://www.dropbox.com/sh/uw6cjqigk2sdwdy/AAAwP55aelyzrYeP1HVUDdMqa?dl=0
And another software project I'm working on as well (a ROM monitor program):
https://github.com/jzatarski/Joe-Mon
10:38 p.m.
On 3/20/2017 2:20 PM, Joseph Zatarski via cctalk wrote:
More info on the hardware I'm using is available
here:
https://hackaday.io/project/6150-beckman-du600-reverse-engineering
I have a copy of
Diab and MQX that would run on it if you have the full
docs. the 68332 was a nice micro
that was used in several projects I worked on. The first one I used an
ice box that was a crude affair
done by an operation in Massachusetts, which allowed in circuit testing
via on chip facilities.
Their development compiler was essentially GCC with a chip startup to
set up the rom, ram etc. registers,
then transfer control to the first instruction of main().
Diab is much like that with a cc setup that prepares the processor, but
the MQX goes and runs much like
your OS sounds. it is initially fixed number of tasks, but can add
tasks, etc. Not really a timeshare type
system, but a pretty powerful embedded OS of course.
I have several boxes with the 68332 and will have to see if your gizmo
would come up and run on it. I'd
need to figure out how to get either an ethernet stack (there are some
out there), or something to
get to a serial mux from our hardware though. I think we have 2mb, and
1mb rom though. Also a
very nice ASIC which was the reason for the hardware.
Nice project
thanks
Jim
22 Mar
22 Mar
12:12 a.m.
Just want to add the thumbs up on your project.
-pete
On Mar 20, 2017 3:38 PM, "jim stephens via cctalk" <cctalk at
classiccmp.org>
wrote:
On 3/20/2017 2:20 PM, Joseph Zatarski via cctalk wrote:
More info on the hardware I'm using is
available here:
https://hackaday.io/project/6150-beckman-du600-reverse-engineering
I have a copy of Diab and MQX that would run on it if you have the full
docs. the 68332 was a nice micro
that was used in several projects I worked on. The first one I used an
ice box that was a crude affair
done by an operation in Massachusetts, which allowed in circuit testing
via on chip facilities.
Their development compiler was essentially GCC with a chip startup to set
up the rom, ram etc. registers,
then transfer control to the first instruction of main().
Diab is much like that with a cc setup that prepares the processor, but
the MQX goes and runs much like
your OS sounds. it is initially fixed number of tasks, but can add tasks,
etc. Not really a timeshare type
system, but a pretty powerful embedded OS of course.
I have several boxes with the 68332 and will have to see if your gizmo
would come up and run on it. I'd
need to figure out how to get either an ethernet stack (there are some out
there), or something to
get to a serial mux from our hardware though. I think we have 2mb, and
1mb rom though. Also a
very nice ASIC which was the reason for the hardware.
Nice project
thanks
Jim
2616
days inactive
2618
days old
3 comments
4 participants
participants (4)
-
jwsmail＠jwsss.com -
jzatar2＠illinois.edu -
kirkbdavis＠me.com -
pete＠petelancashire.com