Random number -> Corresponding LED lit (n00besque content contained)

[Darrel Taylor]

Select Case is a lot like a "Load of IF's" with a few differences.

1. It removes some of the (n00besque content contained) look and feel.
2. Only the first "CASE" that evaluates TRUE will execute, then it exits the SELECT block.
   In your list of IF's, if the first one is true, it still goes on and evaluates all the other IF's too.
   This allows more complex logic, where more than one test can be true, but only the first one is acted on.

The same functionality using IF statements would look like this ...

IF MYBYTE = 1 THEN
    HIGH LED1
ELSE
    IF MYBYTE = 2 THEN
        HIGH LED2
    ELSE
        IF MYBYTE = 3 THEN
            HIGH LED3
        ELSE
            IF MYBYTE = 4 THEN
                HIGH LED4
            ELSE
                IF MYBYTE = 5 THEN
                    HIGH LED5
                ELSE
                    IF MYBYTE = 6 THEN
                        HIGH LED6
                    ENDIF
                ENDIF
            ENDIF
        ENDIF
    ENDIF
ENDIF

OR, if you have PBP 2.60 you could do it like this ...

IF MYBYTE = 1 THEN 
    HIGH LED1
ELSEIF MYBYTE = 2 THEN 
    HIGH LED2
ELSEIF MYBYTE = 3 THEN 
    HIGH LED3
ELSEIF MYBYTE = 4 THEN 
    HIGH LED4
ELSEIF MYBYTE = 5 THEN 
    HIGH LED5
ELSEIF MYBYTE = 6 THEN 
    HIGH LED6
ENDIF

It may not seem like much difference with this simple example, but with large SELECT CASE blocks using more complex comparisons, it can save a boat load of execution time not having to evaluate every condition.

* SELECT CASE is also much easier to read. Especially when it's not your program.

PicBasic Pro, was written to generate the Smallest and Fastest code possible. As it is the HIGH/LOW statements only use a couple of instruction cycles. If you add in the abilities to use them like array's and access pins non-contiguously, it would make EVERY HIGH/LOW statement Bigger and Slower, breaking everyone's code, and causing more complaints than not having those abilities produces.