#STPC: Step a byte or character
Use this macro to generate inline code to increment or decrement (also referred to as step) a 1-byte value at a specified location.
Last updated
- Changed for PUT11.
- Changed for PUT07.
- Changed for PUT05.
- Changed for PUT00.
Format
- reg1
- is a working register for the macro.
- number
- is the amount by which to increment or decrement the specified value. If you specify a positive number, the value at the specified location will be incremented. If you specify a negative number, the value at the specified location will be decremented.
- location
- is the label of the area that contains the value to be incremented or decremented.
Entry requirements
None.
Return conditions
- The contents of reg1 are overwritten.
- Control is returned to the next sequential instruction.
Programming considerations
- If AMODE=64 is coded on the BEGIN macro, all 8 bytes of a register are used.
- For information about macro register conventions, see Assembler program register conventions.
- All labels used in the SPM conditional expression can be no more than 32 characters long. Any additional characters are truncated.
- In a tightly coupled environment, use care when changing common storage. It is possible that more than one program can change a value at the same time. Use the #STPF macro when updating shared storage to ensure the field is updated consistently.
Examples
- In the following example, the value in the byte at EBW033 is incremented by 10.
#STPC R0,10,EBW033 - In the following example, the value in the byte at EBX008 is decremented by 4.
#STPC R14,-4,EBX008