Basic Micro Studio Syntax Manual

GOSUB
Syntax
gosub label{[argument1,...,argumentN]}{,DataResult}
• Label - the go to label of the subroutine to be executed.
Commands
• Argument - is user defi ned arguments to send to the called subroutine. The only limit to the
amount of arguments used is program memory.
• DataResult - is an optional variable to store the value returned from called subroutine.
Supported
• BA - Supported
• BAN - Supported
• BAP - Supported
• BAP40 - Supported
Description
The GOSUB command will jump to a specifi ed label. After executing the code at the jump label a
RETURN command is then used to return the program to the next command after the last called
GOSUB.
If you are familiar with some BASIC languages there is typically a limit to what is called nesting. This
is where multiple GOSUB...RETURN statements are nested inside of each other. There is no limit to
this with Basic Micro Studio other than the size of the available stack memory.
GOSUB stores the address of the next command on the stack and jumps to the specifi ed label. User
specifi ed arguments can be defi ned in the subroutine. A return value from the subroutine can be
stored in the variable that is specifi ed by the GOSUB DataResult argument.
Notes
1. Subroutines should exit via the RETURN command, which clears the saved address from the
stack and returns to the command following the GOSUB. Do not use BRANCH or GOTO when
exiting a subroutine.
2. User defi ned arguments must match the number of arguments defi ned at the subroutine. If they
do not match, a stack overfl ow or underfl ow will happen.
3. If a subroutine returns a value, the GOSUB is not required to use it.
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