$NOMOD51
;------------------------------------------------------------------------------
;  This file is part of the RTX-51 TINY  Real-Time Operating System Package
;  Copyright KEIL ELEKTRONIK GmbH and Keil Software, Inc. 1991-2002
;  Version 2.01
;------------------------------------------------------------------------------
;  CONF_TNY.A51:  This code allows the configuration of the
;                 RTX-51 TINY Real-Time Operating System
;
;  Copy this file to your project folder and add the copy to your uVision2
;  project.  You can customize several parameters of RTX51 Tiny within this
;  configuration file.
;
;  If you use command line tools, translate this file with:
;
;     Ax51 CONF_TNY.A51
;
;  If you use command line tools, link the modified CONF_TNY.OBJ file to 
;  your application with:
;
;     Lx51 <your object file list>, CONF_TNY.OBJ <controls>
;
;------------------------------------------------------------------------------
;
;  RTX-51 TINY Hardware-Timer
;  ==========================
;
;  With the following EQU statements the initialization of the RTX-51 TINY
;  Hardware-Timer can be defined (RTX-51 TINY uses the 8051 Timer 0 for 
;  controlling RTX-51 software timers).
;
;  Define the register bank used for the timer interrupt.
INT_REGBANK	EQU	1	; default is Registerbank 1
;
;  Define Hardware-Timer tick time in 8051 machine cycles.
INT_CLOCK	EQU	20000	; default is 10000 cycles
;
;  Define Round-Robin Timeout in Hardware-Timer ticks.
TIMESHARING	EQU     0	; default is 5 Hardware-Timer ticks.
;		                ; 0 disables Round-Robin Task Switching
;
;  Long User Interrupt Routines: set to 1 if your application contains 
;  user interrupt functions that may take longer than a hardware timer 
;  interval for execution.
LONG_USR_INTR	EQU	0	; 0 user interrupts execute fast.
;                               ; 1 user interrupts take long execution times.
;
;
;------------------------------------------------------------------------------
;
;  USER CODE FOR 8051 HARDWARE TIMER INTERRUPT
;  ===========================================
;
;  The following macro defines the code executed on a hardware timer interrupt.
;
;  Define instructions executed on a hardware timer interrupt.
HW_TIMER_CODE	MACRO
				; Empty Macro by default
		RETI
		ENDM
;
;
;------------------------------------------------------------------------------
;
;  CODE BANKING SUPPORT
;  ====================
;
;  The following EQU statement controls the code banking support for RTX51 TINY.
;
;  Enable or disable code banking support
CODE_BANKING     EQU     1      ; 0 (default) application uses no code banking
;                               ; 1 application uses code banking
;
;------------------------------------------------------------------------------
;
;  RTX-51 TINY Stack Space
;  =======================
;
;  The following EQU statements defines the size of the internal RAM used
;  for stack area and the minimum free space on the stack.  A macro defines
;  the code executed when there is there is not enough free stack on the
;  CPU stack.
;
;  Define the highest RAM address used for CPU stack
RAMTOP		EQU	0FFH	; default is address (256-1)
;
FREE_STACK	EQU	20	; default is 20 bytes free space on stack
;                               ; the value 0 disables stack checking
;
STACK_ERROR	MACRO
		CLR	EA	; disable interrupts
		SJMP	$	; endless loop if stack space is exhausted
		ENDM
;
;
;------------------------------------------------------------------------------
;
;  8051 CPU IDLE CODE
;  ==================
;
;  Many 8051 devices provide an IDLE MODE that reduces power consumption and
;  EMC.  The following macro defines the code executed when there is no 
;  ready task in the system.  The code must set the CPU into an IDLE MODE
;  that stops instruction execution until an 8051 hardware interrupt occurs. 
;

; Disable or Enable CPU_IDLE CODE
CPU_IDLE_CODE   EQU     1       ; 0  CPU_IDLE MACRO is not inserted
                                ; 1  CPU_IDLE MACRO is executed

PCON            DATA    087H    ; Power Control SFR on most 8051 devices

; Stop CPU execution until hardware interrupt; executed when there is no 
; active task in the system. 
CPU_IDLE	MACRO
		ORL	PCON,#1	; set 8051 CPU to IDLE
		ENDM
;
;
;------------------------------------------------------------------------------
;----------------- !!! End of User Configuration Part    !!! ------------------
;----------------- !!! Do not modify code sections below !!! ------------------
;------------------------------------------------------------------------------

; SFR Symbols
PSW     DATA    0D0H
ACC     DATA    0E0H
B       DATA    0F0H
SP      DATA    81H
DPL     DATA    82H
DPH     DATA    83H
TCON    DATA    88H
TMOD    DATA    89H
TL0     DATA    8AH
TL1     DATA    8BH
TH0     DATA    8CH
TH1     DATA    8DH
IE      DATA    0A8H

; TCON
TF1     BIT     8FH
TR1     BIT     8EH
TF0     BIT     8DH
TR0     BIT     8CH
IE1     BIT     8BH
IT1     BIT     8AH
IE0     BIT     89H
IT0     BIT     88H
; IE 
EA      BIT     0AFH
ES      BIT     0ACH
ET1     BIT     0ABH
EX1     BIT     0AAH
ET0     BIT     0A9H
EX0     BIT     0A8H

; Check Configuration Values


		NAME	?RTX51_TINY_KERNAL

PUBLIC	?RTX_CURRENTTASK 
PUBLIC	?RTX_RAMTOP
PUBLIC  os_switch_task
PUBLIC  ?RTX?SET_ISR

EXTRN	NUMBER (?RTX_MAXTASKN)		; max Task Number

?RTX_RAMTOP       EQU   RAMTOP
?RTX_CLOCK	  EQU	-INT_CLOCK

?RTX_REGISTERBANK EQU	INT_REGBANK * 8
		  DSEG	AT    ?RTX_REGISTERBANK
		  DS	2     ; temporary space
?RTX_SAVEACC:     DS	1
saveacc		  EQU	R2    ; for access in interrupt service routine
?RTX_SAVEPSW:     DS	1
savepsw		  EQU	R3    ; for access in interrupt service routine
?RTX_CURRENTTASK: DS	1
currenttask       EQU	R4    ; for access in interrupt service routine

IF (TIMESHARING <> 0)
?RTX_ROBINTIME:   DS	1
robintime	  EQU	R5    ; for access in interrupt service routine
ENDIF

IF (CODE_BANKING <> 0)
EXTRN	DATA	(?B_CURRENTBANK)
EXTRN   CODE    (?B_RESTORE_BANK)
ENDIF


;------------------------------------------------
; Table of Task Entry Pointers
;------------------------------------------------
PUBLIC	?RTX_TASKENTRY

?RTX?TASKENT?S  SEGMENT CODE
		RSEG	?RTX?TASKENT?S
?RTX_TASKENTRY:	DS	2

;------------------------------------------------
; Table of Stack Pointers for each task
;------------------------------------------------
PUBLIC	?RTX_TASKSP

?RTX?TASKSP?S   SEGMENT	IDATA
		RSEG	?RTX?TASKSP?S
?RTX_TASKSP:	DS	1

;------------------------------------------------
; Table of Task Timer/State Pointers
;------------------------------------------------
PUBLIC	?RTX_TASKSTATUS

?RTX?TASKSTATE?S  SEGMENT IDATA
		  RSEG	  ?RTX?TASKSTATE?S
?RTX_TASKSTATUS:
TimerVal:	DS	1	; Task Timer (Software Timer for each task)
TaskState:	DS	1       ; Task Status (state of each Task)

; Definitions for Bits in Task State
;  TaskState.0  = Wait for Signal
;  TaskState.1  = Wait for TimeOut
;  TaskState.2  = Signal Flag
;  TaskState.3  = TimeOut Flag
;  TaskState.4  = Task Ready (Wait for Running)
;  TaskState.5  = Task Active (enabled with os_create)
;  TaskState.6  = Round Robin Time Out
;  TaskState.7  = Run Flag

; byte mask definitions
K_SIG	        EQU	1
K_TMO	        EQU	2
SIG_EVENT	EQU	4
TMO_EVENT	EQU	8
K_READY		EQU	16
K_ACTIVE	EQU	32
K_ROBIN		EQU	64
K_IVL           EQU     128  ; not a task state bit; only used in os_wait
RDY_EVENT       EQU     128  ; READY status flag
K_RDY           EQU     128

; bit position definitions
B_WAITSIG	EQU	0
B_WAITTIM	EQU	1
B_SIGNAL	EQU	2
B_TIMEOUT	EQU	3
B_READY		EQU	4
B_ACTIVE	EQU	5
B_ROBIN		EQU	6
B_IVL           EQU     7    ; not a task state bit; only used in os_wait
B_RDY           EQU     7


IF (TIMESHARING OR CPU_IDLE_CODE)
?RTX?BITS	SEGMENT	BIT
		RSEG	?RTX?BITS
ENDIF

IF (TIMESHARING)
?RTX_TS_DELAY:	DBIT	1       ; Status bit set when task switch in progress
ENDIF

IF (CPU_IDLE_CODE)
?RTX_ISR_SIG:	DBIT	1	; Status bit set when interrupt or os_set_signal
ENDIF


		CSEG	AT	0BH
                JMP	TIMERINT

?RTX?CODE       SEGMENT CODE
                RSEG	?RTX?CODE
		USING	0		; Registerbank 0 for following code

IF (FREE_STACK <> 0)
?RTX_STACKERROR:
                STACK_ERROR             ; User defined Stack Error Code
ENDIF

HW_TIMER:	HW_TIMER_CODE

TIMERINT:

IF (LONG_USR_INTR)
		PUSH	ACC
		MOV	A,PSW
		ANL	A,#018H
		XRL	A,#?RTX_REGISTERBANK
		JNZ	CONT_TIMINT
; avoid recursive timer interrupt
		POP	ACC
		RETI		; Return from Recursive Timer Interrupt
CONT_TIMINT:    POP	ACC

ENDIF

		CALL	HW_TIMER	; Enable Interrupts again.

		MOV	?RTX_SAVEPSW,PSW
		MOV	PSW,#?RTX_REGISTERBANK
		MOV	saveacc,A
; Update 8051 Interrupt Timer
		CLR	TR0
		MOV	A,TL0
		ADD	A,#LOW (?RTX_CLOCK + 7)
		MOV	TL0,A
		MOV	A,TH0
		ADDC	A,#HIGH (?RTX_CLOCK + 7)
		MOV	TH0,A
		SETB	TR0

IF (FREE_STACK <> 0)
; Check if enough free stack is available
		MOV	A,currenttask
		ADD	A,#?RTX?TASKSP?S+1
		MOV	R0,A
		MOV	A,@R0
		CJNE	currenttask,#?RTX_MAXTASKN,checkstack
		MOV	A,#RAMTOP
checkstack:	CLR	C
		SUBB	A,SP
		CJNE	A,#FREE_STACK,$+3
		JC	?RTX_STACKERROR
ENDIF

; Update & Check Task Timers
		MOV	R1,#?RTX_MAXTASKN+1
		MOV	R0,#?RTX?TASKSTATE?S
TIMERLOOP:	DEC	@R0          ; Decrement timer
		MOV	A,@R0
		INC	R0           ; advance to TaskState
		JNZ	NoTimeout
		CLR	EA
		MOV	A,@R0
		JNB	ACC.B_WAITTIM,NoWaitTimeout
		ORL	A,#(K_READY+TMO_EVENT)
		MOV	@R0,A
NoWaitTimeout:  SETB	EA
NoTimeout:	INC	R0           ; advance to TaskTimer
		DJNZ	R1,TIMERLOOP

		MOV	A,saveacc
		MOV	PSW,savepsw
		USING	0		; Registerbank 0 for following code

IF (TIMESHARING == 0)
; Round Robin Task Switching not required.  System Interrupt ends here
?RTX?SET_ISR:	
IF (CPU_IDLE_CODE)
                SETB	?RTX_ISR_SIG
ENDIF
		RET	
ENDIF

IF (TIMESHARING)
; Round Robin Task Switching required.  Check if task generates timeout
; Check for Round Robin Timeout on the current task
		JNB	?RTX_TS_DELAY,CheckRobinTime
NoRobinTimeout:	
?RTX?SET_ISR:	
IF (CPU_IDLE_CODE)
                SETB	?RTX_ISR_SIG
ENDIF
                RET	
CheckRobinTime: DJNZ     ?RTX_ROBINTIME,NoRobinTimeout

?RTX_TASKSWITCHING:
		PUSH	ACC
		PUSH	PSW
		PUSH	B
		PUSH	DPH
		PUSH	DPL
		PUSH	AR0
		PUSH	AR1
		PUSH	AR2
		PUSH	AR3
		PUSH	AR4
		PUSH	AR5
		PUSH	AR6
		PUSH	AR7
IF (CODE_BANKING <> 0)
		PUSH	?B_CURRENTBANK
ENDIF

		MOV	A,?RTX_CURRENTTASK
		RL	A
		ADD	A,#?RTX?TASKSTATE?S+1
		MOV	R0,A
		MOV     A,#K_ROBIN
		CLR	EA
		ORL	A,@R0
		MOV	@R0,A
		SETB	EA
IF (CODE_BANKING <> 0)
		SJMP    os_switch_task1
ENDIF
ENDIF

;------------------------------------------------
; Perform a Task-Switch
;  void os_switch_task (void)
;      uchar i;
;      uchar limit;

;---- Variable 'current' assigned to Register 'R6' ----
;---- Variable 'next' assigned to Register 'R7' ----
;---- Variable 'i' assigned to Register 'R0' ----
;---- Variable 'limit' assigned to Register 'R5' ----
;
;------------------------------------------------

os_switch_task:

IF (CODE_BANKING <> 0)
		PUSH	?B_CURRENTBANK
ENDIF

os_switch_task1:

;      next = current;
IF (TIMESHARING <> 0)
		SETB	?RTX_TS_DELAY		; Delay Task Switching
ENDIF
		MOV	A,?RTX_CURRENTTASK
		MOV	R7,A
;      while (1)  {
		RL	A
		ADD	A,#?RTX?TASKSTATE?S+1
		MOV	R0,A
?C0001:
;        if (++next == MAXTASKN+1)  next = 0;
		INC     R7
		INC	R0
		INC	R0
IF (CPU_IDLE_CODE)
		MOV	A,R7
		CJNE	A,?RTX_CURRENTTASK,NoIDLE
		JBC	?RTX_ISR_SIG,NoIDLE
		CPU_IDLE          ; CPU sleep
NoIDLE:
ENDIF
		CJNE    R7,#?RTX_MAXTASKN+1,?C0003
		MOV	R7,#0
		MOV	R0,#?RTX?TASKSTATE?S+1
?C0003:
;        if (STATE[next].st & K_READY)  break;
		MOV     A,@R0
		JNB     ACC.B_READY,?C0001
;      }
;

PUBLIC	?RTX_NEXTID
PUBLIC  ?RTX_NEXTTASK

?RTX_NEXTID	EQU	AR7
?RTX_NEXTTASK:	NOP		; for Debugging

;      while (current < next)  {
?C0005:
		MOV     A,?RTX_CURRENTTASK
		CLR     C
		SUBB    A,R7
		JNC     ?C0011

;        current++;
		INC	?RTX_CURRENTTASK
;        i = STKP[current];
		MOV     A,#?RTX?TASKSP?S
		ADD     A,?RTX_CURRENTTASK
		MOV     R0,A
		MOV     A,@R0
		MOV     R5,A
;        STKP[current] = SP;
		MOV     @R0,SP
;        if (current == MAXTASKN) limit = RAMTOP;
		INC	R0
		MOV	A,@R0
		MOV	R6,?RTX_CURRENTTASK
		CJNE	R6,#?RTX_MAXTASKN,?C0007
		MOV	A,#RAMTOP
?C0007:
		XCH	A,R5
		MOV	R0,A
;        else                       limit = STKP[current+1];
;
;        while (i != limit)  {
?C0009:
		MOV     A,R0
		XRL     A,R5
		JZ      ?C0005
;          SP++;
;          i++;
;          STACK[SP] = STACK[i];
		INC	R0
		MOV	A,@R0
		PUSH	ACC
		SJMP    ?C0009
;        }
;      }
?C0011:
;
;      while (current > next)  {
		MOV     A,?RTX_CURRENTTASK
		SETB    C
		SUBB    A,R7
		JC      ?C0012
	
		MOV	A,?RTX_CURRENTTASK
		ADD	A,#?RTX?TASKSP?S+1
		MOV	R0,A
		MOV	A,@R0
;        if (current == (MAXTASKN)) i = RAMTOP;
;        else                       i = STKP[current+1];
		MOV	R6,?RTX_CURRENTTASK
		CJNE	R6,#?RTX_MAXTASKN,?C0013
		MOV	A,#RAMTOP
?C0013:
		MOV	R5,A
;        limit = STKP[current];
		DEC	R0
		MOV	A,@R0
		XCH	A,R5
		MOV	R0,A
;
;        while (SP != limit)  {
?C0015:
		MOV     A,SP
		XRL     A,R5
		JZ      ?C0016
;          STACK[i] = STACK[SP];
;          i--;
;          SP--;
		POP	ACC
		MOV	@R0,A
		DEC	R0

		SJMP    ?C0015
?C0016:
;        }
;        STKP[current] = i;
		MOV	A,?RTX_CURRENTTASK
		ADD	A,#?RTX?TASKSP?S
		XCH	A,R0
		MOV	@R0,A
;        current--;
		DEC	?RTX_CURRENTTASK
		SJMP	?C0011
?C0012:
;      }

;      RoundRobinTime = ?RTX_TIMESHARING
IF (TIMESHARING)
		MOV	?RTX_ROBINTIME,#TIMESHARING
ENDIF
         
;       if (STATE[current].st & K_ROBIN)  goto RobinOn;
		MOV	A,?RTX_CURRENTTASK
		RL	A
		ADD	A,#?RTX?TASKSTATE?S+1
		MOV	R0,A
		MOV	R7,#SIG_EVENT
		CLR	EA
		MOV	A,@R0
IF (TIMESHARING)
		JBC	ACC.B_ROBIN,RobinOn
ENDIF
;       if ((STATE[current].st & K_SIG) && (STATE[current].st & SIG_EVENT)
;          goto SignalOn;
                JNB	ACC.B_WAITSIG,SignalOff
		JBC	ACC.B_SIGNAL,SignalOn
SignalOff:
;       if ((STATE[current].st & K_TMO) && (STATE[current].st & TMO_EVENT)
;          goto TimeOutOn;
                MOV     R7,#0		; No Event
		JNB	ACC.B_WAITTIM,NoEvent
		JNB	ACC.B_TIMEOUT,NoEvent
TimeOutOn:	
		MOV	R7,#TMO_EVENT
		ANL	A,#0F4H
SignalOn:
NoEvent:	CLR	ACC.B_RDY	; Clear RDY bit
		XCH	A,@R0
		SETB	EA

		ANL	A,#K_RDY
		ORL	AR7,A
IF (TIMESHARING <> 0)
  IF (CODE_BANKING)
                POP	ACC
		CALL	?B_RESTORE_BANK
  ENDIF
		CLR	?RTX_TS_DELAY
		RET
ELSE
  IF (CODE_BANKING)
                POP	ACC
		JMP	?B_RESTORE_BANK
  ENDIF
		RET
ENDIF
		
		

;------------------------------------------------
IF (TIMESHARING <> 0)
RobinOn:	MOV	@R0,A
		SETB	EA
IF (CODE_BANKING)
		POP	ACC
		CALL	?B_RESTORE_BANK
ENDIF
		POP	AR7
		POP	AR6
		POP	AR5
		POP	AR4
		POP	AR3
		POP	AR2
		POP	AR1
		POP	AR0
		POP	DPL
		POP	DPH
		POP	B
		POP	PSW
		POP	ACC
		CLR	?RTX_TS_DELAY
		RET			; Restart Task
ENDIF
;    }
;  }



;------------------------------------------------
; Start RTX-51 Tiny Kernel
;------------------------------------------------

EXTRN CODE (?C_STARTUP)
PUBLIC	main

main:		MOV	R0,#?RTX?TASKSP?S
		MOV	@R0,SP
		MOV	A,#?RTX_MAXTASKN
		JZ	main2
		MOV	R7,A
main1:		INC	R0
		MOV	@R0,#RAMTOP
		DJNZ	R7,main1
main2:		MOV	R7,#?RTX_MAXTASKN+1
		CLR	A
		MOV	R0,#?RTX?TASKSTATE?S
main1x:		MOV	@R0,A
		INC	R0
		MOV	@R0,A
		INC	R0
		DJNZ	R7,main1x
		MOV	R0,#?RTX?TASKSTATE?S+1
		MOV	@R0,#K_ACTIVE+K_READY
		MOV	DPTR,#?RTX?TASKENT?S
		MOV	A,#1
		MOVC	A,@A+DPTR
		PUSH	ACC
		CLR	A
		MOVC	A,@A+DPTR
		PUSH	ACC
IF (TIMESHARING <> 0)
		MOV	?RTX_ROBINTIME,#TIMESHARING
ENDIF
		ORL	TMOD,#01H	; Timer 0 Mode 1
		MOV	TL0,#LOW (?RTX_CLOCK)
		MOV	TH0,#HIGH (?RTX_CLOCK)
		SETB	TR0
		SETB	EA
		SETB	ET0
		RET		; Start Task 0


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

PUBLIC ?RTX_TASKIDX
?RTX_TASKIDX:	DB	?RTX_MAXTASKN		; for Debugging

                END