[vcf-midatlantic] Woohoo!

Dan Roganti ragooman at gmail.com
Sun Jul 30 11:08:29 EDT 2017


glad to see you make the jump to hyperspace ;)

When you get more practice with this,
I would suggest using a 6502 cross-assembler, Apple emulator,
There's many cross-assemblers for the 6502 that can do the job
Both tools have been supported greatly over the decades,
and just about any editor on your laptop will do with typing in the code
Plus it lets you code anywhere you want, on the desktop, or laptop, or
anywhere you go, without being limited.
It's very practical and relaxing to have that freedom to code anywhere you
go.
And especially when your code starts to get much larger,
eg. you have a bigger viewing screen to work with, to see more than 25
lines, etc
all of your programming tools are at your fingertips,
eg, don't need to use ADTPro every time on your Apple ][

The benefit of the cross-assembler allows you to build your code on some
other desktop/laptop,
1st. because its faster, 2nd, you have more resources. 3rd, cause its cool
:)
You might say it''s being spoiled, But think back to the Altair Basic,
that code was built on a PDP-10 because of these reasons [maybe not the 3rd]
there's a whole story about the method they used, its a good read
and so it will output 6502 machine code directly into a file that's
compatible for your vintage computer.
Remember, then I would would just use Ciderpress to build a Prodos disk
image and send that to you, after coding with the editor on laptop,
but I also recall you can just send the *.src.o file via ADTPro, so you can
use the same floppy disk if it has enough space

>From your last Lego Robot project this past winter, I found a lot of
support for the emulators,
especially when all I had within arm's reach was my laptop during my last
recovery.
The one limitation I had then was that the emulators didn't support many of
the external interfaces,
such as that 9750 Lego Robot Interface box, so I had to build some
workarounds in the code

about printing Text on the screen,
There are many of these assemblers and cross-assemblers which have a
feature called Macro's
This is not specific to a computer platform, just the developer who wrote
the code for the assembler
I use dozens of Macro's for my C64 assembly code,
Basically these are the same snippets of code you find in the various
examples, like others mentioned here,
but then you have to convert the code somewhat so it conforms with the
other Macro's, it's a type of software interface,
This is sort of like writing a subroutine, which relies on certain
variables to pass the information to compute.
But then each of these Macro's use the 6502 registers to pass this
information, and sometimes a value in a memory address,
And the conforming process defines how you make use of the 6502 registers
One can be used as the input variable, another would be the output
variable, etc, etc
At the same time, it reduces the amount of code you have to type, or even
copy/paste.
And these handful of Macro's would be kept in a separate "Include" file,
you should learn this in a later chapter in that book.
Because when you build your code,
the assembler will automatically insert this snippet of code from the
Include file which contains your Macro,
directly into spot of the your code where you called it.
This is just an overview, there should be more info in that book to explain
this in more detail

about what Mike said,
definitely use comments, that might sound like an old fart's reason,
but it was common practice 30++yrs ago, not sure how it's regarded in
today's work environment,
but I've noticed nobody has the same thought about this anymore.
It was mostly because somebody that came after you on the job, when they
had to update or fix the code,
and if they had to spend more than enough time to rethink about why you
create some function or subroutine
that's spent money on the company's time, and so the boss didn't like to
see time wasted,

because 6mons or more from now, when you take a break or worked on another
project,
and mainly for personal benefit, and when your code gets larger, and then
you go back to that previous project,
there might be some code in there, not the obvious stuff, but some code
which you had to brainstorm and create,
and you find yourself having to rethink what or why you created it, this
can get annoying sometimes,
it's very easy for code to look obfuscated, even when you didn't try :) but
also with your own creations,
unless you add comments to describe the purpose, or reason, or what its
for, or why i did this, etc, etc
you don't need a paragraph in there, but maybe just a couple of lines,
all depending on how much work it took you to create that snippet of code

about searching for books,
my first goto place is always with archive.org
plus there's still 2nd,3rd,4th sources as well
recall when we were online just the other day, I immediately mentioned it's
available on there
I'm glad to see they had this one too
Dan
excuse my rambling



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