In SX Microcontrollers, SX/B Compiler and SX-Key Tool, Sparks-R-Fun wrote:

Kramer,

   I agree.  Creating a menu for the first time would be much easier in SX/B than trying to create one from scratch in assembler!  So I would start there.

   Here is how I would do it.  First I would create the desired logic structure in SX/B.  Then, if I needed to present it in assembly language I would use CTRL-L to list the assembly output.  Then I would modify the code produced to fit the rest of my assembly program.

   For example, to process a single byte value as a menu selection I would use the SX/B command [b]LookDown[/b] to check for a valid menu selection followed by a [b]Branch[/b] statement to go to the portion of my code that handles that menu selection.

   Borrowing from an example in the SX/B help files...

[CODE]LOOKDOWN Menu_Selection, "F", "B", "S", Menu_Index   ' compare against valid commands

BRANCH Menu_Index, Forward, Backward, Stop_Bot       ' execute valid command [/CODE]

Becomes...

[CODE]MOV __PARAM1,#-1               ;    LOOKDOWN Menu_Selection, "F", "B", "S", Menu_Index     ' compare against valid commands

INC __PARAM1                  
CJNE Menu_Selection,#"F",@$+7 
MOV Menu_Index,__PARAM1       

INC __PARAM1                  
CJNE Menu_Selection,#"B",@$+7 
MOV Menu_Index,__PARAM1       

INC __PARAM1                  
CJNE Menu_Selection,#"S",@$+7 
MOV Menu_Index,__PARAM1       


    
MOV __PARAM1,Menu_Index        ;  BRANCH Menu_Index, Forward, Backward, Stop_Bot       ' execute valid commands

TEST __PARAM1                 
JZ @Forward                   

DEC __PARAM1                  
JZ @Backward  
                
DEC __PARAM1                  
JZ @Stop_Bot      [/CODE]


If you examine this example for a while you should be able to figure out how it works.  You need to change the variables, the menu options and the branch locations to fit your program.  That should not be too difficult.  90% of the menu processing work is already done for you!

 - Sparks

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