AGD Key Location Search Tool

AGD Key Location Search Tool - by Mulder 2010



This program is designed to help you add joystick support and re-definable key

options to games made with Jonathan Cauldwell's 'Arcade Game Designer'.



It works by searching for the following code in the game code...



LD A,x

CALL zzzzz



Once it finds such an event in the code, it will display a message with

information about it so that you can look at it and decide if it might be

related to key detection.



First, load in the Search Tool and then insert the tape of your raw AGD game

code. It should load the code automatically and then display a menu.



Press 1 to start a search.



Now, you'll be waiting a while, so make a cup of tea!



After some time, information will start to appear on the screen...



Address - This is printed in yellow and is the address you need to poke when

setting up joystick controls or new keys.



Value - Preceded with V=, this is the byte value at the address.



Key - Preceded with K=, this is the byte value represented as a Key value.



Routine Address - Preceded with AD=, this shows the address where the CALL jumps

to.



At some point, the screen may get full (you'll see the Scroll? prompt). It's a

good idea to grab a pen and paper here. You should know what keys are used in

your game and what they do. Any time one of these keys appears in the list on

the screen, write down the yellow address, the value of the byte, the function

which the key represents (up, down, left, right, fire, whatever), and the

routine address.



Press enter to continue the search, it will remove the scroll prompt.



When the search is over, it will beep for 5 seconds, then you can press any key

to go back to the menu.



Now, go to the Table of Key Values.



Decide what new keys you want the game to use (they could be 67890 for Sinclair

Joystick or 56780 for Cursor, whatever you like).



Now, write down the values for these new keys next to the functions they will

represent on your piece of paper for every address you noted down.



Find the most common Routine address which is associated with ALL your keys on

your paper and now, note down all the yellow addresses that are associated with

it, they key direction for each one and the new key value for each one.



Stop the Search tool with BREAK.



Now, poke the new values into the yellow addresses.



Test the game. This can often be done with RANDOMIZE USR 35800, but other start

addresses may be valid depending on the version of AGD you used to make the

game, etc...



Did your new keys work? Yes? Then thoroughly test the game to make sure they

work in all situations possible. If this is the case, your work is done, you

know how to change the controls in your game!



If no, then go back to your notes. Which Routine address is the next most

common? Do the same for this address, note down all the yellow addresses that

are associated with it, they key direction for each one and the new key value

for each one. Now poke all those yellow addresses with their new values, and

start the game again...



Did your new keys work? Yes? Then thoroughly test the game to make sure they

work in all situations possible. If this is the case, your work is done, you

know how to change the controls in your game!



If no, then you can repeat the previous steps for less and less common routine

addresses until the new keys work.



If the game crashes during testing, then it's likely that you've poked a false

positive that has appeared in the list with one of your old keys associated with

it. Strike off the last set of addresses you poked and don't poke them again.

You'll need to poke all of the other addresses that didn't cause the crash again

after re-loading the game code.





EXAMPLE:



I loaded a game into the tool and did a search



The search turned up these results....



For routine address 37816

45584 left

45595 right

45617 left

45647 fire

45679 right

45745 fire

45777 up

45788 fire



For routine address 37792

47437 up

47518 up

47538 down

47572 right

47638 left

47760 fire



Now, ALL my keys were associated with the routine at 37792, even though that's

not the most common routine. So, I poked those addresses with new key values

first.



This did not work, so I the poked all the addresses for 37816 as that was the

most common and was at least associated with most of my keys. This did work, so

I knew that I had found all the addresses I needed to poke.



It's useful to have the old values for the addresses handy, e.g. you will

probably want an option in your game menu that sets them back to normal for

keyboard control after somebody has selected joystick and then wants to play

with keys again.