Configuration Using Other DOS Packages, Extpages Reserve

The Last Word 3.0 Reference Manual

assuming there were at least four free banks on the target machine – LW would allocate one bank for the macro/paste/directory buffer (which it always does when using extended memory, before allocating any other banks as text buffers), three banks for extra text buffers, and it would enlarge the main text buffer to 19K.

The RESERVE instruction is intended to allocate banks of extended memory for use by machine code extensions. It’s envisaged that in the future, applications such as proofreaders and table of contents generators will be written as extensions for LW. The extensions load at $3300 and must first have space allocated for them with the EXTPAGES statement, which merely allocates the specified number of 256 byte memory blocks (to a maximum of 12) above $3300 to house the executable code of extension programs (this memory is taken from the 19K main text buffer: extensions are only available when LW is using BANKED memory).

EXTPAGES 4

RESERVE 1

The above statements in LW.SYS will reserve four pages of RAM from main memory at $3300 for extension code, and a single bank of extended RAM for use by extensions which require it. If there is insufficient extended memory, or if LW is not using banked memory, these instructions will have no effect.

Another example:

BANKED ON

BANKS 1,2,3,4,5,6

RESERVE 1

EXTPAGES 8

On a 320K machine running DOS 2.5 with a 64K RAMdisk installed, the LW.SYS file above will configure LW with four extended text buffers, and one bank for the macro/paste/directory buffers, reserving a single bank (actually the last in the list) for use by extensions. Since LW is using banked memory, the main text buffer would be 19K. However, the EXTPAGES statement has reserved 8 pages (2K) at $3300 for use by extension executable code, reducing the size of the main text buffer to 17K.

You can disable banked memory use altogether by including the following line in LW.SYS:

BANKED OFF

This will cause LW to ignore any BANK, EXTPAGES or RESERVED statements in LW.SYS. The main (and only) text buffer will be 16K in size and the paste, macro and directory buffers will each be only 1K long. This is the same configuration LW will adopt when run on a standard 64K XL/XE machine.

8.3.2 CONFIGURATION USING OTHER DOS PACKAGES

When LW is loaded on a system using an unsupported DOS (anything other than SpartaDOS X and DOS 2.5 or MyDOS with the standard RAMdisk drivers), it makes no assumptions about whether the operating system is using extended memory for RAMdisks or other purposes. Therefore the default behaviour of the program under these circumstances is NOT to use banked memory. To use banked memory when

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XL specifications

The Atari XL series, launched in 1982, represented a significant evolution in home computing, building upon the foundation laid by the Atari 400 and 800 systems. This line of computers included popular models such as the Atari 600XL and 800XL, both of which combined affordability with robust capabilities, making them attractive options for home users, educators, and enthusiasts alike.

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