There are the following breakpoint and callback services:
| Service | Description |
| Allocate_V86_Call_Back | Allocates a V86-mode callback. |
| Allocate_PM_Call_Back | Allocates a protected-mode callback. |
| Call_When_VM_Returns | Installs a return-from-interrupt callback. |
| Install_V86_Break_Point | Installs a breakpoint callback. |
| Remove_V86_Break_Point | Removes a V86 breakpoint. |