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; Copyright (c)2022 Jeremy Seth Henry

; All rights reserved.

;

; Redistribution and use in source and binary forms, with or without

; modification, are permitted provided that the following conditions are met:

;     * Redistributions of source code must retain the above copyright

;       notice, this list of conditions and the following disclaimer.

;     * Redistributions in binary form must reproduce the above copyright

;       notice, this list of conditions and the following disclaimer in the

;       documentation and/or other materials provided with the distribution,

;       where applicable (as part of a user interface, debugging port, etc.)

;

; THIS SOFTWARE IS PROVIDED BY JEREMY SETH HENRY ``AS IS'' AND ANY

; EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED

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; DISCLAIMED. IN NO EVENT SHALL JEREMY SETH HENRY BE LIABLE FOR ANY

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;

;------------------------------------------------------------------------------

; Sample Task Manager application

;

; Revision History

; Author          Date     Change

;---------------- -------- ---------------------------------------------------

; Seth Henry      7/15/22  Initial Release

;-----------------------------------------------------------------------------

;------------------------------------------------------------------------------

; This application requires the following build parameters in the Open8 CPU

;  core to function correctly:

;

; Allow_Stack_Address_Move => true  RSP may relocate/retrieve the SP->R1:R0

; Enable_Auto_Increment    => true  Indexed load/store instructions can use

;                                    auto-increment feature when Rn is odd

;                                    (or Rn++ is specified).

; BRK_Implements_WAI       => true  BRK is interpreted as a WAI

; Enable_NMI               => true  Interrupt 0 is not maskable

; Sequential_Interrupts    => true  ISRs are NOT interruptable

; RTI_Ignores_GP_Flags     => true  RTI restores only lower 4 ALU flags

; Supervisor_Mode          => true  I-bit is restrictive

; Unsigned_Index_Offsets   => true  LDO/SDO treat offset as UNSIGNED

; Rotate_Ignores_Carry     => true  Rotate instrs do not use the carry

; Default_Int_Mask         => x"00" CPU starts with only the NMI active

;

; Further note - NOP is mapped to BRK in the assembler. Do NOT use NOP with

;  the BRK_Implements_WAI enabled, as the NOP will instead trigger WAI.

;------------------------------------------------------------------------------

;------------------------------------------------------------------------------

; BNI is used as a BRA (branch always) in user-mode code, since the I-bit

;  should never be set. There are checks in each task's main loop that verify

;  that this bit is cleared, and will panic the system otherwise.

; Similarily, in code running in the supervisor context, the I bit should

;  always be set, potentially allowing BRI to be used as a BRA. Note that this

;  isn't inherently safe, as ISR's are allowed to clear the I bit themselves

;  while user-mode code can't affect the I-bit.

;------------------------------------------------------------------------------

;------------------------------------------------------------------------------

; Include block - add all of the other source files here

;

; Note that the order of included files is important due to the way the

;  assembler works. Any constant which is used to derive another constant must

;  be defined first. The exception is creating pointer tables, which occurs on

;  a later pass.

;------------------------------------------------------------------------------

.INCLUDE "sys_hw_map.s"      ; System Memory Map (HDL <> ASSY)

.INCLUDE "sys_const.s"       ; System-Wide Constants

.INCLUDE "sys_version.s"     ; System software version

.INCLUDE "taskmgr_config.s"  ; Task manager cconfiguration constants

.INCLUDE "taskmgr_const.s"   ; Main task scheduler constants

.INCLUDE "task_0_const.s"    ; Task 0 Constants & Macros

.INCLUDE "task_1_const.s"    ; Task 1 Constants & Macros

.INCLUDE "taskmgr_func.s"    ; Main task scheduler & ISR code

.INCLUDE "task_0_func.s"     ; Task 0 Executable

.INCLUDE "task_1_func.s"     ; Task 1 Executable

;------------------------------------------------------------------------------