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[File] JSW Keypad Trimmer

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#1 Spider


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Posted 26 July 2017 - 04:53 PM

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File Name: JSW Keypad Trimmer

File Submitter: Spider

File Submitted: 26 Jul 2017

File Category: Tools and Patches

System: Sinclair
Original Author(s): Andy Ford


A simple Basic program to remove the Keypad data completely from the JSW game code. Load in your game code, load the 'trimmer', run it and save the game code afterwards.


Two versions are provided:


1. The basic keypad only version. This replaces the long pointless startup routine with a much shorter (32 bytes vs 10 bytes) and removes the following:


The keypad messages "Enter code at grid location etc" - 64 bytes starting 34187
The keypad reading/display routines - 156 bytes starting 34463
The keypad graphics and attributes - 255 bytes starting 39680
The codes themselves - 178 bytes starting 40448


Note this does not remove (most) of the 'garbage data' sat in the sprite editing area as its not all stritcly keypad related. For that see (2) below...


2. The slightly extended version. This does not remove any 'unused routines' , it merely expands slightly on the above as some random data is present in the sprite area, this will remove it too. See the screenshot of the before/after for this. It is not recommended to use this one on a third party game before checking said areas have not already been recycled for sprite or other data however it is recommended to use this on a standard game before editing it. To clarify this, as well as the above the following are also emptied:


Source remnant - 64 bytes starting 39936
Data remnant - 333 bytes starting 40627
Data remnant - 1152 bytes starting 42624


Click here to download this file

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#2 Spider


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Posted 26 July 2017 - 04:55 PM

To slightly clarify on this:


The 'keypad remover' is safe on third party games unless the area has been recycled already. It would be prudent to check this. it is provided for this purpose.


The 'expanded' one is the one to use in 99% of cases as this removes the keypad as the 'remover' plus the garbage data (easily seen in JSWED) from the sprite area. This is the one to use on an original game before editing. It is likely to work on the majority of third party games too. Here is a comparison picture of the relevant section of the sprite area from JSWED when the 'expanded' one has been used:




And two quick pics (in the download descriptor anyway) of it 'in action'


Keypad only:



Keypad and remnant:



It should be noted no other 'unused' or otherwise data is removed, this 'extra' was merely to assist in the initial tidy up of the sprite area, nothing more. :)

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#3 Spider


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Posted 26 July 2017 - 06:10 PM

A new level (level 0) was added to the 'Builder' file:


Last Updated --


This 'new' level is intended to show the Trimmer action as such. No other code routines were removed. Details are available in that linked listing.

Changing order to chaos since 1984

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