h6. [[OS SWI Calls]] h6(. » [[OS_ChangeEnvironment]] h6((. » Escape Handler h2. Escape Handler |_<^{width:4em}. Entry | | |/3<^. R11|<^. Bit 6: | | 0 => Escape condition is being cleared/acknowledged | | 1 => Escape condition is being set | |<^. R12|<^. "workspace" - don't use the value 1 | |<^. R13|<^. SVC/IRQ stack | |<^. |<^. SVC or IRQ mode, IRQs+FIQs undefined | |_<^{width:4em}. Exit|_<^. | |<^. R12|<^. 1 to set callback | |<^. R0-R11|<^. Preserved | h4. Use This handler allows programs to control how Escape events are handled. h4. Notes This is called whenever an escape condition is detected and the [[Escape Event|escape event]] is disabled (except for calls to [[OS_Byte 125]] which always call the handler). [[OS_Byte 124]] and [[OS_Byte 126]] will also result in the handler being called with R11 bit 6 clear to clear/acknowledge an escape condition. If the handler returns with R12=1, a [[OS_SetCallBack|non-transient callback]] will be queued. h4. See also * [[Escape Event]] * [[OS_Byte]] * [[OS_Byte 124]] * [[OS_Byte 124]] * [[OS_Byte 126]] * [[OS_Byte 153]]