[Coco] How much memory

Richard E. Crislip rcrislip at neo.rr.com
Sun Nov 28 15:14:05 EST 2010

On Saturday 27 November 2010 15:25:00 Frank Swygert wrote:
> I agree with Aaron. Fast memory that OS-9/Nitros-9 can use would be 
> One little nit though -- BASIC can't address 512K, not without a lot of
> modification anyway. BASIC is still limited to 64K without bank 
> some of the RAM or using some other tricks. A RAM drive was a nice 
way to
> utilize the full 128/512K or RAM in a CC3 and speed things up at the 
> time. A program could then be written in a modular form and 
> modules as needed quickly. That was one trick I used in "CoCo Family
> Recorder", a modular genealogy program. At least I seem to recall 
> that... was a long time ago!
> --------------
> Date: Fri, 26 Nov 2010 22:21:43 -0500
> From: Aaron Wolfe<aawolfe at gmail.com>
> On Fri, Nov 26, 2010 at 9:48 PM, Becker, 
Gary<Gary.Becker at amd.com>  wrote:
> > >  I was just wondering, how much memory could a CoCo3 
realistically use.
> > >  BASIC can only address 512K. NitrOS-9 can address a lot more, 
but it
> > >  has a fixed amount of system resources and after they are 
used, any
> > >  additional RAM is wasted. A RAM drive is a good way to utilize a
> > >  bunch of additional RAM. Compiling C programs from a RAM 
drive is
> > >  definately a lot faster than from a HDD. Which of these three 
> > >  is better?
> > >  
> > >  1 1.5 Meg of memory that is able to run at 25 MHz.
> Assuming we are talking about CoCo3FPGA, I vote for option 1.  As 
> mentioned, with OS9 it is difficult to actually consume 512k with
> processes to start with, due to limited space in the system page.
> There is OS9 L3 and/or maybe some future projects that would open 
> the system area enough to use more ram for processes.  If so, it 
> be preferable to have this ram be fast as possible.
> IMHO, a ram drive just isn't much use when the CPU is 25Mhz and 
> primary storage is 460kbps..  everything is very, very quick without 
> ram drive.   I would not give up any "fast ram" that may be useful for
> processes in exchange for a ram drive.
> > >  2 512K at 25 MHz and 8 or more Meg for a RAM Drive that can 
> > >  accessed at 3.5 MHz or less.
> > >  
> > >  3 Eight or more Meg of RAM that can be accessed at 3.5 MHz or 
> > >  
> > >  Please limit to these three options.
> > >  
> > >  Gary

That's How I did it with an address database I modified from the 
Rainbow. It is also the trick I used to modify a geography program from 
the Rainbow. That program drew the outline of states and you got to 
guess its capatol. I copied the addresses of the finished drawings as 
bitmap to disk and loaded them rather than allowing the program to 
draw it. It went much faster.

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