XOS-C.DOC  by Paul Globman (C) 1989
               [72227,1661]


     XOS - X-bank Operating System
             (cross-bank)

XOS is a system of three programs that is designed to run in LOMEM of each of
the T200's 3 RAM banks.  These three programs load/install as one program 
interact with one another in such a way that you can have the software of all 3
banks available in any bank.  XOS uses the first 768 bytes in each bank.

XOS runs in the location used by Disk Power 200.  With XOS installed, Disk 
Power cannot be used and any attempt to use it could have disastrous results.

Installing XOS is simply a matter of 1) loading XOSLDR.CO and XOSDAT.CO into
the same RAM bank, 2) HAVE AT LEAST 1K FREE RAM IN EACH BANK TO INSTALL XOS, 
3) run XOSLDR.CO, and 4) run XOSLDR.CO again (the second execution of
XOSLDR.CO is sometimes needed in a cold started system... run it twice at all 
times to insure proper installation).

NOTE: XOSLDR.CO and XOSDAT.CO Are available as XOS-C.200, and you will
need HXFER.200 to convert the ASCII files into XOSDAT.CO and XOSLDR.CO.


XOS was designed to offer cross-bank abilities (as well as other 
enhancements) to the Tandy 200 at the MENU, with BASIC, TEXT, and TELCOM.

  ==================================
MENU and TEXT enhancements:

XOS will enhance the operation of Menu functions, also offering several TEXT 
utilities like background printing and cross-bank cut/paste.

At the Menu, ADRESS and SCHEDL have been made invisible, and the LABEL line
will display up to 7 new functions in addition to the original 3.  The new 
LABEL line will look like this:

          Cmd>           Name File     
Bank Back Roms Copy Kill Pste Prnt Menu
 [1]  [2]  [3]  [4]  [5]  [6]  [7]  [8]

F2 - REVERSE BANK SWITCHING - press F2 to go to menu of previous bank.

F3 - ROMS - press F3 for ROM selection menu.  Modify the use of F3(Roms) with
XOSUTL.BA (provided).

F3 - CMD> - press F3 with cursor over BASIC to run a BASIC program.  If the 
cursor is NOT over BASIC, then F3 will run a .CO file.

If CAPS LOCK is on, then the file to be executed will default to 3:CMD>.BA or
3:CMD>.CO, depending upon where the cursor was.

If CAPS LOCK is off, then you will be prompted "Cmd>".  Just type in a 
filename (no extension) and press enter.  "3:" is the default bank and needs 
no prefix.  Filename may begin with "1:" or "2:" to indicate file location, if 
not in bank #3.

F6 - PASTE BUFFER TRANSFER - move the paste buffer to another bank for 
cross-bank CUT and PASTE operation.

F6 - RENAME - rename program or file under cursor.  Allows illegal 
characters and filenames, so use caution.

F7 - BACKGROUND PRINTING - press F7 with cursor over DO file.  This duplicates 
SAVE TO LPT: from text.  Once begun, press F7 to abort.  Beep announces 
start and stop of print task.  Printing will be suspended if you switch banks,
switch LOMEM code (F8), or edit a file that is in lower RAM than the file that
is printing.  Backgroung printing will resume when the conditions are restored
to normal.

F7 - FILES DISPLAY - press F7 to view the remaining two banks, displayed in 
circular order (1,2,3,1,2), with current bank active for various MENU 
functions.  Shift-F7(File) will restore the normal Menu display.

F8 - ADDITIONAL MENU OPTIONS - this will offer the additional options listed 
for F3, F6, and F7.

  ===================================
BASIC enhancements:

In BASIC, F8 has been re-defined to CALL 40961, which will re-install all XOS 
hooks, should they become dis-engaged.  This can also be accomplished from 
BASIC with the following command...

KEY8,"Menu"+chr$(24)+"CALL40961"+chr$(13)

XOS will enhance BASIC and M/L capabilities by allowing programmers to
write programs that access other RAM banks.  The BASIC enhancements will 
allow a running program to RUN a BASIC program, LOADM a .CO file, or KILL a 
TEXT.DO file in another bank.

The instruction, CALL 41179, will load XBAS-2 into the ALT LCD buffer of the 
current bank.  Once CALLed, 

XBAS-2 is used by the BASIC programmer to access files in other banks.  Data 
files (.DO files) in other banks can be KILLed, and BASIC and M/L programs can 
be brought in from other banks and executed in the current bank.

Once the BASIC program has executed the "CALL 41179" command, the routines can 
be accessed with the following call:

    CALL 63600,CMD,VARPTR(X$)

The commands are 7 - KILL FILE.DO
                 8 - LOADM FILE.CO
                 9 - RUN FILE.BA

XBAS-2 does internal error checking and will beep if there is a problem.  
XBAS-2 will not execute the wrong instruction and offers the BASIC 
programmer a result descriptor byte so the BASIC program can trap and handle 
problems.  The result descriptor (RD) byte is at 61302, and can be PEEKED 
either before or after a CALL to XBAS-2.

KILL FILE
This command is: F$="2:FILE.DO"
                :CALL63600,7,VARPTR(F$)

The RD byte is 0 if the file is found and killed.  The RD byte will retain 
the CMD if the CALL is not sucessful, and a beep will sound.  During program
debugging, a non zero RD means the file was not specified as .DO, the CMD was 
not a seven (7), or the file to be killed, was not found.


LOADM FILE.CO
This command is: 

 F$="2:FILE.CO":CALL 63600,8,VARPTR(F$)

If RD=0 then the .CO file was loaded into place and the execution address is
stored at 61303/61304.

The load address is stored at 61300/61301.  If these two bytes are both 0 
then the file was not found.  Otherwise 61300/61301 has the load address of the
file and HIMEM has to be cleared for this file to LOADM.


RUN FILE.BA
This command is: 

 F$="2:FILE.BA":CALL 63600,9,VARPTR(F$)

Your program will load and run the BASIC program F$, so if the program making 
the call continues, then F$ wasn't found.  The RD would reflect the command 9.

For all XBAS-2 commands, the user must check RD and pointer addresses, 
IMMEDIATELY after the CALL 63600.

The original XOS offered XBASIC.  To retain the features of XBASIC you must 
store XBASIC.CO in bank #3.  Now the following code is the equivalent of 
LOADM"XBASIC".

10 CALL 41179             'LOADM XBAS-2
20 X$="3:XBASIC.CO"       'SPECIFY FILE
30 CALL63600,8,VARPTR(X$) 'LOADM XBASIC
40 IFPEEK(61302)<>0THEN99 'TEST LOAD

Now XBASIC is loaded and CALL 63600 is available with commands 1 thru 6.  A 
simple CALL 41179 will reload XBAS-2 for commands 7,8, and 9.

BASIC programs are brought into the unsaved program buffer, and executed by
IPL of the unsaved buffer progradisastIC programs called in by the CMD> 
key should begin with the IPL"" statement to prevent it from unwanted 
execution.

Attempts to alter the POWER time setting must be followed by POKE 40962.  Ex:

 10  POWER 100:POKE40962,100
 20  POWER CONT:POKE40962,0

  =================================
TELCOM enhancements:

XOS adds the following to TELCOM's TERM mode...

  F6 = display files and bytes
  F6+SHIFT = direct access to TEXT
  F7 = jump to TELCOM in next bank
  F7+SHIFT = jmp TELCOM in prev. bank

XOS will allow you to jump from bank to bank while on-line with either
an external or internal modem.  And whichever bank you jump to, the hooks
are active to allow you to switch banks again.

The TELCOM hook code runs in the last 15 file slots of the directory of each 
bank.  This means that you can have a maximum of 31 files per bank, instead 
of 46.  From the T200 users I have spoken to, this is not a problem.

In return for the 15 file sacrifice you get several excellent TELCOM 
enhancements.

NOTE: The first time you enter TELCOM in another bank, you will enter the TERM
mode by pressing F4(Term).  Should you exit this bank, and re-enter it, you 
will have to type TERM<ENTER> if F4(Term) doesn't work.

Each time you press F3(Cmd>) at the Menu, the TELCOM hooks will be reset in
all three banks so the XOS features are active, in the same way F8 from BASIC 
restores the XOS menu hook.  Programs that alter the TELCOM hooks can now be 
used without concern.

  =================================
YOUR CUSTOM 200

I have given XOS the ability to be customized.  F3 comes with "Roms" and 
"Cmd>" as its default utilities.  The "Roms" function key can be made to 
offer direct access to your OPTION ROM(s).

The "Cmd>" function key can be made to load and run default programs that are 
named CMD>.BA and CMD>.CO in Bank #3 by maintaining CAPS LOCKed.  Unlocking 
CAPS will allow user input to determine file to run.

The following XOSUTL.BA will allow the redefining of F3(Roms) for your 
individual use.  Note... UR-2 may disengage the XOS hook.  BASIC F8 will
restore the XOS hook as it returns to the Menu.  Use this to access the NODE 
ROM and keep XOS engaged.

If you run XOSSAV.CO (with XOSDAT.CO in RAM), the current modified F3(Roms) 
will be saved to XOSDAT so future loads of XOSDAT will not require any further
modification.

 =====================================
Acknowledgements:

James Yi [73327,1653] for part of the LOMEM adjustment code.

Randy Hess [73267,552] for beta testing and feedback.
 =====================================
 USE HXFER.CO TO CREATE XOSSAV.CO

With XOSDAT.CO on the menu, run XOSSAV.CO to modify XOSDAT so it 
reflects CURRENT status.

70F8480070F811AEF83E0ACD4F6ECAD232CD8C6E2806F3AFCD91F83E04CD91F83E08CD91F8FBC9329CF80100032100A0C50600D5CDB19B7AD112C123130B79B0
C29AF8C9584F534441542E434F00

=======================================
0 REM XOSUTL.BA   Copyright (c) 1989
5 REM              by Paul Globman
10 REM Utility Module
20 M=INSTR("n",CHR$(PEEK(41024)))
30 IF M<>1 THEN BEEP:MENU
40 CLS:PRINT:PRINT"You are about to ";
50 PRINT"modify XOS module #"M:PRINT
60 PRINT"The label above [F3] is...  ";
70 FORI=1TO4:P$=P$+CHR$(PEEK(41001+I))
80 NEXT:PRINTP$:PRINT:PRINT
90 GOTO 1000
100 REM -------------------- MAKE F3=X$
105 FOR I=1 TO 4
110 POKE 41001+I,ASC(MID$(X$,I,1)):NEXT
115 RETURN
1000 REM ------------------------ XOS-1
1005 RESTORE 1010:X$="Roms":GOSUB100
1006 FORI=0TO76:READA:POKE41563+I,A
1007 NEXT:GOTO1020
1010 DATA 205,150,79,33,56,162,205,204
1011 DATA 17,42,63,245,34,116,162,42,65
1012 DATA 245,34,122,162,205,23,155,33
1013 DATA 11,244,34,63,245,33,79,244,34
1014 DATA 65,245,33,1,160,34,61,245,175
1015 DATA 50,30,253,50,72,248,33,140
1016 DATA 162,229,205,3,139,208,254,5
1017 DATA 208,245,62,240,33,181,242,1
1018 DATA 11,0,22,46,190,194,168,162,54
1019 DATA 0
1020 PRINT" 1 - TS-DOS
1030 PRINT" 2 - ANY OTHER ROM
1040 PRINT" 3 - 8 ROM PACK
1050 PRINT" 4 - 8 ROM PACK / ROMDISK
1060 PRINT
1070 PRINT" 5 - NO ROM
1080 PRINTSTRING$(30,"-"):PRINT
1090 PRINT" Option => ";
1093 O$=INPUT$(1):IFO$=""THEN1095
1095 O=VAL(O$):IFO<1ORO>5THEN1095
1098 ON O GOTO 1100,1200,1300,1400,1500
1100 REM ----------------------- TS-DOS
1105 RESTORE 1190:POKE41528,0
1110 FORI=1TO13:READA:POKE41562+I,A
1120 NEXT:X$="Disk":GOSUB100:MENU
1190 DATA 175,50,30,253,219,216,230
1195 DATA 12,246,2,205,239,238
1200 REM -------------------- OTHER ROM
1210 REM use for UR-2, SuperRom, ROM2
1220 POKE41528,0
1230 FORI=0TO3:POKE41605+I,0:NEXT
1240 PRINT"Enter 4 character "
1250 PRINT"         F3 label :";
1251 LINEINPUTX$
1260 IF LEN(X$)<>4THEN1250
1270 GOSUB100:MENU
1300 REM ----------------------- ROMPAK
1310 POKE41621,5:GOTO1450
1400 REM ---------------------- POMPAK+
1410 POKE41621,6
1450 REM --------------------- ROM line
1455 R$="Rom2 UR-2 Super Disk TWrd Romdsk":CLS:PRINT:PRINT:PRINT
1457 IFO=3THENR$=LEFT$(R$,25)
1460 PRINT"Create your own ROMs option"
1461 PRINT"      line below...":PRINT
1462 PRINT:PRINT"Press <enter> to use sample line...
1465 PRINT@560,R$:LINEINPUTR2$
1466 IF R2$=""THEN R2$=R$
1470 R2$=LEFT$(R2$+SPACE$(32),32)
1475 FORI=1TO32
1480 POKE41527+I,ASC(MID$(R2$,I,1))
1485 NEXT:MENU
1500 REM ----------------------- NO ROM
1505 RESTORE 1530
1510 FORI=1TO3:READA:POKE41562+I,A
1520 NEXT:X$="    ":GOSUB100:MENU
1530 DATA 195,129,160