Altair Emulator enhancements - progress report - questions - test-drb@ccmp.vtda.org

12 Sep 2000

From: James Willing &lt;jimw(a)agora.rdrop.com&gt;
To: Cini, Richard &lt;RCini(a)congressfinancial.com&gt;

...
 The paper-tape based versions of Altair BASIC polled
the 'sense switches'
...
 to determine the type of I/O to be used, and by
inferrence the port
numbers.  It contained its own I/O routines. 

Casette versions polled the sense switches (port FFh) as well.

...

  What port locations were generally used to
service
 serial ports used for console I/O? 
The closest thing to a 'standard' selection (also used in the disk based
versions of BASIC) was for the 2-SIO board which was located at ports 20
and 21 (octal). 

Or the MITS SIOA and SIOB at 0/1 with one of two possible status bit
combos.  THe SIO had a early rev that move the sense bits around.

...
   Does anyone
have a working set of CP/M
 binaries that I can load into the emulator? 
For what disk sub-system?  (Mits, Tarbell, etc...???) 

Do you plan to emulate the BIOS IO to the ports and disk system?

Allison