Jump to content
IGNORED

ProDOS and BASIC version combinations?


Keatah

Recommended Posts

Forgive an ignorant question from a non-Apple II guy (though I have used them of course).  What was different in BASIC between ProDOS versions?  I thought Applesoft ran from ROM, and I know that DOS intercepts the input/output to look for DOS commands with the CHR$(4) notation.  Is it just that part of BASIC that changed?  

Link to comment
Share on other sites

He is referring to Basic.system, not Applesoft Basic.  Basic.system is like DOS3.3 where it handles all the CHR$(4) commands in Basic programs, prompt commands, and file creation and management.  All Prodos knows how to do is to Read from and Write to a device.

 

Basically Basic.system puts all the commands to access devices into English words.

Link to comment
Share on other sites

Yes. It doesn't replace Applesoft in ROM. I tend to call it an interceptor/interposer rather than interpreter, because interpreter in old-school terms means the entire BASIC language is interpreted real-time on the fly as a program runs. Semantics I suppose!

 

At any rate, https://archive.org/details/beneath-apple-dos-prodos-2020

..is a good read and reference.

 

Link to comment
Share on other sites

12 hours ago, Casey said:

Forgive an ignorant question from a non-Apple II guy (though I have used them of course).  What was different in BASIC between ProDOS versions?  I thought Applesoft ran from ROM, and I know that DOS intercepts the input/output to look for DOS commands with the CHR$(4) notation.  Is it just that part of BASIC that changed?  

The reason for "breaking" ProDOS into Two parts, is that if your making a Machine Language Program, you can Unload the BASIC.SYSTEM from Memory to give you more RAM....

 

MarkO

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...