FreeRTOS/Source/portable/Paradigm/Tern_EE/large_untested/portasm.h

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*/

typedef void tskTCB;
extern volatile tskTCB * volatile pxCurrentTCB;
extern void vTaskSwitchContext( void );

/*
 * Saves the stack pointer for one task into its TCB, calls
 * vTaskSwitchContext() to update the TCB being used, then restores the stack
 * from the new TCB read to run the task.
 */
void portSWITCH_CONTEXT( void );

/*
 * Load the stack pointer from the TCB of the task which is going to be first
 * to execute.  Then force an IRET so the registers and IP are popped off the
 * stack.
 */
void portFIRST_CONTEXT( void );

#define portSWITCH_CONTEXT()										 \
						asm { mov	ax, seg pxCurrentTCB		} \
							asm { mov	ds, ax						}  \
							asm { les	bx, pxCurrentTCB			}	/* Save the stack pointer into the TCB. */    \
							asm { mov	es:0x2[ bx ], ss			}   \
							asm { mov	es:[ bx ], sp				}   \
							asm { call  far ptr vTaskSwitchContext	}	/* Perform the switch. */   \
							asm { mov	ax, seg pxCurrentTCB		}	/* Restore the stack pointer from the TCB. */  \
							asm { mov	ds, ax						}   \
							asm { les	bx, dword ptr pxCurrentTCB	}   \
							asm { mov	ss, es:[ bx + 2 ]			}      \
							asm { mov	sp, es:[ bx ]				}

#define portFIRST_CONTEXT()												\
							asm { mov	ax, seg pxCurrentTCB		}	\
							asm { mov	ds, ax						}	\
							asm { les	bx, dword ptr pxCurrentTCB	}	\
							asm { mov	ss, es:[ bx + 2 ]			}	\
							asm { mov	sp, es:[ bx ]				}	\
							asm { pop	bp							}	\
							asm { pop	di							}	\
							asm { pop	si							}	\
							asm { pop	ds							}	\
							asm { pop	es							}	\
							asm { pop	dx							}	\
							asm { pop	cx							}	\
							asm { pop	bx							}	\
							asm { pop	ax							}	\
							asm { iret								}