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Path: utzoo!watmath!clyde!burl!mgnetp!ihnp4!nsc!nessus
From: nessus@nsc.UUCP (Kchula-Rrit)
Newsgroups: net.micro.ti
Subject: Use of CALL LINK in XBASIC
Message-ID: <1196@nsc.UUCP>
Date: Wed, 18-Jul-84 21:19:14 EDT
Article-I.D.: nsc.1196
Posted: Wed Jul 18 21:19:14 1984
Date-Received: Thu, 19-Jul-84 05:00:35 EDT
Organization: The Patriarchy ot Kzin
Lines: 53


     You may remember me; I am the person that built the homebrew 32K expansion
RAM for my TI 99/4A.  Well, I built a parallel printer port(pseudo-Centronics to
control a TRS-80 plotter/printer) on the same board with a 2K RAM in place of
the Device Driver ROM.  I have another question:

     In my Editor/Assembler Manual, Section 17.1.2.2 tells how to set up a
linkage between Console BASIC and low Expansion RAM.

     "...

     You can use the LOAD subprogram to load a program directly into memory.
However, you must enter the program name in the REF/DEF table so that the
program can be run with the Link subprogram(described in Section 17.1.3).

     To enter the program name in the REF/DEF table, use the PEEK subprogram
(described in Section 17.1.4) to find the values at addresses >2028 and >202A. 
These addresses contain the First Free Address in Low memory(FFAL) and Last Free
Address in Low memory(LFAL), respectively.  These values must differ by at least
eight bytes to have space for your program name and address.  Change LFAL to a
value eitght less than its old value, and then load the program name, up to six
bytes, starting at the new LFAL address, followed by two bytes which give the
starting address of the program.  For example, suppose LFAL is >3F38, your
program name is OBJ1, and starts at address >8300.  Change LFAL to >3F30 and
load OBJ1, two spaces, and >83 00 into addresses >3F30 through >3F37 with the
statement

     CALL LOAD(16176,79,66,74,49,32,32,131,00)

     ..."

     The manual has info for linking to XBASIC, but is very vague on the
subject.  Does anyone out there know how to link from XBASIC to machine-code
programs?  My XBASIC manual is next to useless on this matter.  It just
refers "the user to the manual(s) accompanying the machine-code program".
My system contains the console, XBASIC cartridge, speech synthesizer, RAM board,
and a cassette recorder.  I got the manual to increase my store of info about
the computer.  They sold it to me for ~8->10 dollars.  It {seems to} explain the
instruction set reasonably well.  I send this to the net for the purposes of
discussion; it should generate some.  I am going to try some more playing with
the system; maybe a hex dump of low Expansion RAM is in order.  I will post
what I find.

                                           Kchula-Rrit
                                           !menlo70!nsc!nessus

:-)"Why don't you stay for the night,
    Or maybe a byte;
    I could show you my latest obsession.
    I've been making a RAM
    With 4K and some more,
    And its great for creating my tension.":-)