The SET ASSEMBLER and SET DISASSEMBLY commands

The SET ASSEMBLER ON and SET DISASSEMBLY ON commands enable some of the same functions. However, you must consider which type of CUs that you will be debugging (assembler, disassembly, or both) before deciding which command to use. The following guidelines can help you decide which command to use:

• If you are debugging assembler CUs but no disassembly CUs, you might want to use the SET ASSEMBLER ON command. If you need the following functions, use the SET ASSEMBLER ON command:
  • Use the LIST, LIST NAMES CUS, or DESCRIBE CUS commands to see the name of disassembly CUs.
  • Use AT APPEARANCE to stop z/OS® Debugger when the disassembly CU is loaded.
  If you don't need any of these functions, you don't need to use either command.
• If you are debugging a disassembly CU, you must use the SET DISASSEMBLY ON command so that you can see the disassembly view of the disassembly CUs. The SET DISASSEMBLY ON command enables the functions enabled by SET ASSEMBLER ON and also enables the following functions that are not available through the SET ASSEMBLER ON command:
  • View the disassembled listing in the Source window.
  • Use the STEP INTO command to enter the disassembly CU.
  • Use the AT ENTRY * command to stop at the entry point of disassembly CUs.

If you are debugging an assembler CU and later decide you want to debug a disassembly CU, you can enter the SET DISASSEMBLY ON command after you enter the SET ASSEMBLER ON command.