SpartaDOS X Reference Manual

The Command Processor — Commands

Index

This command is recognized by the command processor as an internal command that chains to the external program "CAR.COM", so both the CAR and BASIC commands share the same external program. CAR.COM is memory resident while you are in the BASIC environment, so MEMLO will be slightly higher during this period.

SpartaDOS X has a MEM.SAV facility somewhat like that of Atari DOS 2, but much more powerful. The environment variable "BASIC" should be set to the file you wish to use as the memory-save file for BASIC. If no such environment variable exists, then the memory-save feature is disabled. If this feature is disabled, BASIC will be entered cold (there will be no program in user memory).

The default value of the "BASIC" variable is "I:>BAS.SAV". You of course may change this with the SET command, for example:

    SET BASIC=D8:BASIC.SAV

sets the variable to "D8:BASIC.SAV". To see the current value of "BASIC" (and all the other environment variables) just type:

    SET

and to clear the variable (i.e. disable the BASIC memory-save feature) type

    SET BASIC

(See the SET command for a further explanation.)

With the memory-save feature enabled, if a problem is encountered when loading or saving the memory file (BASIC.SAV by default), an error message will appear. If this happens while loading the memory file, you will be prompted with the old MEMLO (when the file was saved). If an error exists while saving the memory file, you will be notified of that. In either case, you will have the option to abort and correct the problem or to proceed, deleting the memory file. Press the <ESC> key if you wish to abort or <RETURN> to proceed. More detail of the two situations that can occur follows:

• Upon entering BASIC, the current MEMLO does not match the MEMLO in the memory-save file. This can occur after installing extra drivers since last time you entered BASIC (such as the keyboard buffer, RAMDISK, etc), or LOADing commands such as X or COMMAND (see the LOAD command). At this point you may press <ESC> and restore the system to the way it was when you last entered BASIC (By COLD starting and/or LOADing programs), or press <RETURN> and enter BASIC cold. This will also happen if the memory-save file has somehow been corrupted.
• Upon exiting BASIC (using the DOS command), the disk fills up or is not online and the memory-save file can't be saved. You have the option to go to DOS (RETURN) and lose the current BASIC program in memory, or to go back to BASIC (ESC) and SAVE whatever you were working on or clear up the disk problem.

In addition to saving the contents of user memory, the memory-save feature saves page 0 (from $80-$FF), and pages 4-6. This means that you may alternate between BASIC and CARtridge without losing what you were working on. When you enter BASIC the memory-save file is loaded, allowing you to edit a BASIC program, go to DOS, reboot the computer, and enter BASIC with exactly what you were working on before rebooting the system (as long as the memory-save file is present and valid).

Performing a cold start (a jump to $E477) while in BASIC will cause the SpartaDOS X cartridge and the external cartridge plugged into the SpartaDOS X cartridge, if any, to be disabled. This will have the same effect as typing COLD /N from the command processor.

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