April/May 1980, Issue 7

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BASIC extra & Memory mapping update


The Nascom 8K Microsoft Basic does not support any kind of ‘Format statement’, such as ‘PRINT USING’, a fact which can be annoying if you wish to produce a column of figures. For example, if you wish to produce a list of items and prices and the prices are say ... 12.00, 6.56, 145.02, 0.32 ... then using the straight forward ‘PRINT’ command this would appear as:– rather than:–

12 12.00
6.56 6.56
145.02 145.02
.32 0.32

One way to obtain the column on the right is to use a subroutine to do the formatting for you. The Basic supports a good set of string functions that makes the implementation of such a subroutine a fairly simple matter. An example of such a routine is given below. The variable A (amount) has to be set to the amount (in pounds) to be printed before the subroutine is called. It returns with the formatted output in A$. It works for both positive and negative numbers.

MEMORY MAPPING – more information

Following the article on memory mapping in the last INMC newsletter (No. 6), here are some brief details of memory usage in the area 0C00H – 0CFFH, which is intended for use as workspace for the operating system software and your own programs if you are desparate.

– 0C00H – 0C7FH NAS-SYS work space. See NAS-SYS manual for details.

– 0C80H – 0CFFH Possible extended system workspace. 00C90H – 0CFFH is used by the repeat keyboard routine which is listed in INMC newletter No. 6.

– 0D00H – 0DFFH Workspace for possible future system software, is also used for Naspen stack and ‘Find string’ space.

– 0E00H – 0EFFH Workspace for NAS-DIS and D-BUG, including D-BUG stack.

– 0F00H – 0FFFH Workspace for ZEAP, followed by the user. stack (0F80H – 0FFFH).

There is no reason why areas of RAM should not be used for different purposes by different pieces of software. The above usage of 0D00H – 0FFFH is applicable in the machine code/​assembler programming environment. Once in Basic, 0D00H – 0F80H is free for you to POKE or DOKE your machine routines into. We recommend that you use 0D00H upwards for these – we doubt you will run out of space since most of these routines are only about 30 bytes long and we have seen one which was two bytes long!

This is an OCR’d version of the scanned page and likely contains recognition errors.

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