I don't understand why they don't have a datasheet. It isn't rocket
science. However, there are a lot of strengths to this part.
It is available.
It is fast. I am merging MIDI streams while scanning my bass pedals
and sending MIDI (at 38,25 kbaud) and display data (at 57,600 kbaud)
and running timer interrupts at 1 mS. Not bad for basic. I'm not
sure we'd get that kind of performance out of other products and I do
a lot of MIDI processing.
Hardware floating point. I've benchmarked it and it is only slightly
slower than integer performance.
I've verified the on-chip eeprom. I've also verified the I2C input
and output.
Positive and negative edge interrupts. Great for capturing quick
triggers.
The development environment works quite well. I've got no issues with
it. Always reliable.
Reasonable code space. I was a bit concerned about adding 128 defined
strings to display GM MIDI instruments but that program only took 12.5
kbytes and I have 20 kbytes of code space left.
For me, code compatibility is pretty important but that's only because
I have 32 programs and don't feel like figuring out all the nuances of
a new compiler.
On the downside, the interrupts for the 3rd timer don't work in the
current compiler and the include function doesn't work which requires
each program to be stand alone.
As to the reset, they added a power-on reset chip. I guess it is a
nice feature as the PSIM doesn't always reliably reset (I added a
capacitor to mine). This circuit generates a 360 mS reset with fast
edges so you can guarantee that all external devices reset. I assume
it would be described in the data sheet if there were one. My issue
was trying to reset it externally with a switch. Not a good idea on a
totem pole output. I only noticed this as I plugged the part into a
current design PCB that has a reset switch and noticed the difference
in operation.
I actually see few risks with commiting this to copper as many of the
interfaces / timing / etc. have been validated (MIDI, I2C, timer
interrupts, edge interrupts, etc.) but that is just my humble opinion.
Dave
--- In
ComputerVoltageSources@yahoogroups.com, "Grant Richter"
<grichter@...> wrote:
>
> I still don't see a datasheet for the BasicAtomPro28M on the
BasicMicro website.
>
> There are questions about the reset circuitry and if the current dev
system supports the
> additional 4 analog inputs. Dave Brown seems to have one working,
did you find anything
> about the reset problem you were having?
>
> I really have not had the time or money to buy a 28M and hand trace
a schematic and test
> the software.
>
> It seems brash to commit to a copper board with the number of
questions still remaining
> about the processor core itself.
>
> I think issuing a PC board with unresolved technical issues may do
more harm than good.
>
> Grant Richter
>
> --- In ComputerVoltageSources@yahoogroups.com, Harry Bissell Jr
<harrybissell@>
> wrote:
> >
> > Last plan was that Grant was going to fax me a sketch
> > of the CPU schematic and I would draw it... then we
> > will proceed. I have not heard anything since, but
> > he's
> > prlly busy like me :^P
> >
> > H^) harry
> >
> > --- "Larry T." <larry@> wrote:
> >
> > > Hello everyone
> > >
> > > I'm just wondering if there is any kind of status
> > > update on the state
> > > of the main processor PCB layout?
> > >
> > > Larry T.
> > >
> > >
> > >
> > >
> >
>