Patching WordStar for the Acorn Z80 Second Processor

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WordStar patched for use with the Acorn Z80 second processor.
Installing the video driver.
Updating and existing installation.
Patching the installation.
Startup screen showing the new video driver name.

Introduction

This article described the the very simple steps required to patch WordStar 3.0 so that it works as expected on an Acorn BBC Microcomputer with the Acorn Z80 Second Processor. For a similar article relating to dBaseII see Patching dBaseII for the Acorn Z80 Second Processor

Wordstar comes with the program INSTALL.COM, this is used to create the WordStar application (WS.COM) or update it as required. The program requires the user to select the terminal type from a menu of choices. In order to use WordStar with the BBC Micro the None of the Above option should be selected. The installation will continue, e.g. select printer etc., however, at the end when asked Is the Installation Complete, reply N. The installation program will then allow constants (memory locations within WS.COM) to be updated.

Updating these constants as described below will allow WordStar to work with the Acorn BBC Microcomputer with the Acorn Z80 Second Processor.

Terminal Driver

The constants to be updated to support the BBC terminal are shown below, all values are in Hexadecimal;

Screen Size

   Location Value Comment
     0248     20  height 
     0249     50  width

Cursor Control

   Location Value Comment
     024A     01  number of chars in sequence
     024B     1F  sequence char 1
     025D     01  column before row flag 
     025E     00  line offset
     025F     00  column offset

Highlighting On

   Location Value Comment
     0284     04  number of characters in sequence
     0285     11  sequence char 1
     0286     81  sequence char 2
     0287     11  sequence char 3
     0288     00  sequence char 4

Highlighting Off

   Location Value Comment
     028B     04  number of characters in sequence
     028C     11  sequence char 1
     028D     80  sequence char 2
     028E     11  sequence char 3
     028F     01  sequence char 4

Terminal Name

The terminal name is stored in locations 018F to 01AE and can be changed from the default value, which in my case was IBM 3101 Terminal, to something more appropriate. The following overwrites IBM 3101 Terminal with Acorn Z80, note the use of spaces (20h) to pad the string.

   Location Value
     018F     20
     0190     41
     0191     62
     0192     6F
     0193     72
     0194     6E
     0195     20
     0196     5A
     0197     38
     0198     30
     0199     20
     019A     20
     019B     20
     019C     20
     019D     20
     019E     20
     019F     20
     01A1     20
     01A2     20
     01A3     20
     01A4     20
     01A5     20
     01A6     20
     01A7     20
     01A8     20
     01A9     20
     01AA     20
     01AB     20
     01AC     20
     01AD     20
     01AE     20