;*******************************************************************************
; FILENAME	: MODE_Switch1.ASM
; AUTHOR	: SONiX
; PURPOSE	: Test System Mode (Normal mode, Slow mode, Green mode, and Power
;		  down mode) Switching
; REVISION	: 28/01/2003 V1.0	First issue
;*******************************************************************************
;*  (c) Copyright 2003, SONiX TECHNOLOGY CO., LTD.
;*******************************************************************************
CHIP	SN8P1808					; Select the CHIP
//{{SONIX_CODE_OPTION
	.Code_Option	OSG		Enable
	.Code_Option	High_Clk	4M_X'tal
	.Code_Option	High_Clk/2	Enable
	.Code_Option	Watch_Dog	Enable
	.Code_Option	Security	Enable
	.Code_Option	LVD		Enable
	.Code_Option	LCD		Enable
//}}SONIX_CODE_OPTION

;-------------------------------------------------------------------------------
;			Include Files
;-------------------------------------------------------------------------------
.nolist							; do not list the macro file

	INCLUDESTD	MACRO1.H
	INCLUDESTD	MACRO2.H
	INCLUDESTD	MACRO3.H

.list							; Enable the listing function

;-------------------------------------------------------------------------------
;			Constants Definition
;-------------------------------------------------------------------------------
;	ONE			EQU		1

;-------------------------------------------------------------------------------
;			Variables Definition
;-------------------------------------------------------------------------------
.DATA

	org	0h				;Bank 0 data section start from RAM address 0x000
	Wk00B0		DS	1		;Temporary buffer for main loop
	Iwk00B0		DS	1		;Temporary buffer for ISR
	AccBuf		DS	1		;Accumulater buffer
	PflagBuf	DS	1		;PFLAG buffer

	org	100h				;Bank 1 data section start from RAM address 0x100
	BufB1		DS	20		;Temporary buffer in bank 1

;-------------------------------------------------------------------------------
;			Bit Flag Definition
;-------------------------------------------------------------------------------
	Wk00B0_0    	EQU	Wk00B0.0    	;Bit 0 of Wk00B0
	Iwk00B0_1 	EQU	Iwk00B0.1   	;Bit 1 of Iwk00





;-------------------------------------------------------------------------------
;			Code section
;-------------------------------------------------------------------------------

.CODE

	ORG	0				;Code section start
	jmp	Reset				;Reset vector
						;Address 4 to 7 are reserved
	ORG	8
	jmp	Isr				;Interrupt vector

	ORG	10h
;-------------------------------------------------------------------------------
;			Program reset section
;-------------------------------------------------------------------------------
Reset:
	mov	A,#07Fh				;Initial stack pointer and
   	b0mov	STKP,A				;disable global interrupt
    	b0mov	PFLAG,#00h			;pflag = x,x,x,x,x,c,dc,z
	b0mov	RBANK,#00h			;Set initial RAM bank in bank 0
	mov  	A,#40h				;Clear watchdog timer and initial system mode
	b0mov	OSCM,A

    	call 	ClrRAM				;Clear RAM
    	call 	SysInit				;System initial
    	b0bset	FGIE				;Enable global interrupt

;-------------------------------------------------------------------------------
;			Main routine
;-------------------------------------------------------------------------------
Main:
	b0bset	FWDRST				;Clear watchdog timer

	call	MnApp

	jmp	Main

;-------------------------------------------------------------------------------
;			Main application
;-------------------------------------------------------------------------------
MnApp:

	; Put your main program here

;Normal/Slow mode to power down(sleep) mode (Wakeup by P0/P1)
	b0bset	fcpum0				;Set CPUM0=1

;Normal mode to slow mode (The external high-speed oscillator is still running)
	b0bset	fclkmd				;To set CLKMD=1

;Slow mode to normal mode (The external high-speed oscillator is still running)
	b0bclr	fclkmd				;To set CLKMD=0

;Normal mode to slow mode (The external high-speed oscillator stops)
	b0bset	fclkmd				;To set CLKMD=1
	b0bset	fstphx				;To stop external high-speed oscillator

;Slow mode to normal mode (The external high-speed oscillator stops)
	b0bclr	fstphx				;Turn on the external high-speed oscillator
	
	b0mov	z,#27				;If VDD=5V, internal RC=32KHz (typical) will delay
@@:	decms	z				;0.125ms*81=10.125ms for external clock stable
	jmp	@B

	b0bclr	fclkmd				;Change the system back to the normal mode

;Normal/Slow mode to green mode	(Wakeup by P0/P1)
	b0bset	fcpum1				;To set CPUM1=1

;Normal/Slow mode to green mode (Wakeup by T0)
	b0bclr	ft0ien				;To disable T0 interrupt service
	b0bclr	ft0enb				;To disable T0 timer
	mov	a,#20h		
	b0mov	t0m,a				;To set T0 clock=fcpu/64
	mov	a,#74h
	b0mov	t0c,a				;To set T0C initial value=74H (To set T0 interval=10ms)
	b0bclr	ft0ien				;To disable T0 interrupt service
	b0bclr	ft0irq				;To clear T0 interrupt request
	b0bset	ft0enb				;To enable T0 timer

	b0bclr	fcpum0				;To set CPUM1,CPUM0=10 (Go into green mode)
	b0bset	fcpum1	

	ret

;-----------------------------------
;	Jump table routine
;-----------------------------------
	ORG	0x0100				;The jump table should start from the head 
						;of boundary.
	b0mov	A,Wk00B0              
	and	A,#3
	ADD    	PCL,A
	jmp    	JmpSub0
	jmp    	JmpSub1
	jmp    	JmpSub2
;-----------------------------------


JmpSub0:
	; Subroutine 1
	jmp	JmpExit

JmpSub1:
	; Subroutine 2
	jmp	JmpExit

JmpSub2:
	; Subroutine 3
	jmp	JmpExit

JmpExit:
	ret					;Return Main

;-------------------------------------------------------------------------------
; Isr (Interrupt Service Routine)
; Arguments	: 
; Returns	: 
; Reg Change: 
;-------------------------------------------------------------------------------
/*
Processing multi-interrupt request needs to set the priority of these interrupt requests.
The IRQ flags of the 7 interrupt are controlled by the interrupt event occurring. But the
IRQ flag set doesn't mean the system to execute the interrupt vector. The IRQ flags can be
triggered by the events without interrupt enable. Just only any the event occurs and the 
IRQ will be logic "1".
There are two things need to do for multi-interrupt. One is to make a good priority for
these interrupts. Two is using IEN and IRQ flags to decide executing interrupt service 
routine or not.
*/

Isr:
;-----------------------------------
;	Save ACC and system registers
;-----------------------------------
	b0xch	A,AccBuf			;B0xch instruction do not change C,Z flag
	push					; Save 80h ~ 87h system							

;-----------------------------------
;   Check which interrupt happen
;-----------------------------------

INTP00CHK:					; Check INT0 interrupt request
	B0BTS1	FP00IEN				; Check P00IEN
	JMP	INTP01CHK			; Jump check to next interrupt
	B0BTS0	FP00IRQ				; Check P00IRQ
	JMP	INTP00				; Jump to INT0 interrupt service routine
INTP01CHK:					; Check INT1 interrupt request
	B0BTS1	FP01IEN				; Check P01IEN
	JMP	INTP02CHK			; Jump check to next interrupt
	B0BTS0	FP01IRQ				; Check P01IRQ
	JMP	INTP01				; Jump to INT1 interrupt service routine
INTP02CHK:					; Check INT2 interrupt request
	B0BTS1	FP02IEN				; Check P02IEN
	JMP	INTT0CHK			; Jump check to next interrupt
	B0BTS0	FP02IRQ				; Check P02IRQ
	JMP	INTP02				; Jump to INT2 interrupt service routine
INTT0CHK:					; Check T0 interrupt request
	B0BTS1	FT0IEN				; Check T0IEN
	JMP	INTTC0CHK			; Jump check to next interrupt
	B0BTS0	FT0IRQ				; Check T0IRQ
	JMP	INTT0				; Jump to T0 interrupt service routine
INTTC0CHK:					; Check TC0 interrupt request
	B0BTS1	FTC0IEN				; Check TC0IEN
	JMP	INTTC1CHK			; Jump check to next interrupt
	B0BTS0	FTC0IRQ				; Check TC0IRQ
	JMP	INTTC0				; Jump to TC0 interrupt service routine
INTTC1CHK:					; Check TC1 interrupt request
	B0BTS1	FTC1IEN				; Check TC1IEN
	JMP	INTSIOCHK			; Jump check to next interrupt
	B0BTS0	FTC1IRQ				; Check TC1IRQ
	JMP	INTTC1				; Jump to TC1 interrupt service routine
INTSIOCHK:					; Check SIO interrupt request
	B0BTS1	FSIOIEN				; Check SIOIEN
	JMP	INT_EXIT			; Jump to exit of IRQ
	B0BTS0	FSIOIRQ				; Check SIOIRQ
	JMP	INTSIO				; Jump to SIO interrupt service routine


;-----------------------------------
; Exit interrupt service routine
;-----------------------------------

INT_EXIT:

	pop					; Restore 80h ~ 87h system registers			
	b0xch	A,AccBuf			; B0xch instruction do not change C,Z flag

	reti					; Exit the interrupt routine



;-------------------------------------------------------------------------------
;	INT0 interrupt service routine
;-------------------------------------------------------------------------------
INTP00:
	b0bclr	FP00IRQ

	;Process P0.0 external interrupt here

	jmp	INT_EXIT
;-------------------------------------------------------------------------------
;	INT1 interrupt service routine
;-------------------------------------------------------------------------------
INTP01:
	b0bclr	FP01IRQ

	;Process P0.1 external interrupt here

	jmp	INT_EXIT
;-------------------------------------------------------------------------------
;	INT2 interrupt service routine
;-------------------------------------------------------------------------------
INTP02:
	b0bclr	FP02IRQ

	;Process P0.2 external interrupt here

	jmp	INT_EXIT
;-------------------------------------------------------------------------------
;	T0 interrupt service routine
;-------------------------------------------------------------------------------
INTT0:
	b0bclr	FT0IRQ

	;Process T0 internal interrupt here

	jmp	INT_EXIT
;-------------------------------------------------------------------------------
;	TC0 interrupt service routine
;-------------------------------------------------------------------------------
INTTC0:
	b0bclr	FTC0IRQ

	;Process TC0 timer interrupt here

	jmp	INT_EXIT
;-------------------------------------------------------------------------------
;	TC1 interrupt service routine
;-------------------------------------------------------------------------------
INTTC1:
	b0bclr	FTC1IRQ

	;Process TC1 timer interrupt here

	jmp	INT_EXIT
;-------------------------------------------------------------------------------
;	SIO interrupt service routine
;-------------------------------------------------------------------------------
INTSIO:
	b0bclr	FSIOIRQ

	;Process SIO interrupt here

	jmp	INT_EXIT

;-------------------------------------------------------------------------------
;	SysInit
; 	Initialize I/O, Timer, Interrupt, etc.
;-------------------------------------------------------------------------------
SysInit:
	@SET_PUR	0x33			;Set P0, P1, P4, P5 with pull-up resistor

	mov	a,#00h				;Clear P1, P2, P4, P5
	b0mov	p1,a
	b0mov	p2,a
	b0mov	p4,a
	b0mov	p5,a

	mov	a,#00h
	b0mov	p1m,a				;Set P1 to input mode

	mov	a,#00000001b
	b0mov	p1w,a				;Enable P1.0 wakeup function

	ret

;-------------------------------------------------------------------------------
; ClrRAM
; Use index @YZ to clear RAM  (00h~7Fh)
;-------------------------------------------------------------------------------

ClrRAM:

; RAM Bank 0
	clr	Y    				;Select bank 0 
	b0mov	Z,#0x7f				;Set @YZ address from 7fh

ClrRAM10:
	clr	@YZ				;Clear @YZ content
	decms	Z  				;z = z - 1 , skip next if z=0
	jmp	ClrRAM10
	clr 	@YZ				;Clear address 0x00

; RAM Bank 1
	mov	A,#1
	b0mov	Y,A				;Select bank 1
	b0mov	Z,#0x7f				;Set @YZ address from 17fh

ClrRAM20:
	clr	@YZ				;Clear @YZ content
	decms	Z				;z = z - 1 , skip next if z=0
	jmp 	ClrRAM20
	clr 	@YZ				;Clear address 0x100
	ret

;-------------------------------------------------------------------------------
	ENDP