cstartxf.asm

ccp

	JMP	cc_UC, STBINIT		; start bit initialization
BPNZ:					; bit pointer not zero
	MOV	R7, #16			; R7 = 16 
	SUB	R7, BP_RAM		; R7 = 16 - bitpointer
	CMP	R5, R7			; if (initbits < (16 - bitpointer))
	JMP	cc_ULT, LT16		;   then bitblocksize = initbits
	MOV	R9, R7			; bitblocksize = 16 - bitpointer
	SUB	R5, R9			; initbits -= bitblocksize
STBINIT:				; start bit initialization
	MOV	R8, #0FFFFH		; mask = 0XFFFF
	MOV	R6, #00000H		; bitbuffer = 0X0000
	MOV	R10, R9			; i = bitblocksize 	
NBI:					; next bit init
	SHR	R8, #1			; mask >> 1;
	SHR	R6, #1			; bitbuffer >> 1; 
	MOVB	RL7, [SOF_ROM+]		; move initialization data to RL7
					; and initdata++;
	JMP	CC_Z, CLRB		; if ( initialization data == 0 )
					;   then clear bitbuffer.15
	BSET	R6.15			;   else set bitbuffer.15
CLRB:					; R6.15 already zero
	CMPD1	R10, #1			; if ( i != 1 )
	JMP	cc_NE, NBI		;   then i--; next bit init;
					;   else  save bit data block	
	MOV	R7, #16			; R7 = 16
	SUB	R7, R9			; R7 = 16 - bitblocksize
	ADD	R7, BP_RAM		; R7 = 16 - bitblocksize + bitpointer
	SHR	R6, R7			; bitbuffer >> ((16 - bitblocksize ) +
					;                bitpointer)
LOOPMASK:				; mask >> ((16 - bitblocksize ) + 
					; 	    bitpointer)
	CMPD1	R7, #0			;
	JMP	cc_Z, ENDMASK		;
	SHR	R8, #1			; 
	BSET	R8.15			;
	JMP	cc_UC, LOOPMASK		;
ENDMASK:				;
	AND	R8, [SOF_RAM]		; mask &= *bitdata;
	OR	R6, R8			; bitbuffer |= mask;
	MOV	[SOF_RAM], R6		; *bitdata == bitbuffer;
	ADD	SOF_RAM, #2		; bitdata += 2;
	MOV	BP_RAM, #0		; bitpointer = 0;
	CMP	R5, #0			; if( initbits != 0) 
	JMP	cc_NZ, NBBI		;   then continue bit initialization
					;   else end of bit initialization
@IF( @EQS( @MODEL, "SMALL" ) )
	MOV 	DPP1, #PAG ?BASE_DPP1	; restore data page register DPP1 and
	MOV 	DPP2, #PAG ?BASE_DPP2	; DPP2 to their default values.
@ENDI
	JMP	CC_UC, INIT		; next initialization
					;
@ELSE					; NO BIT INITIALIZATION
					;
INIT_01:
	ADD	R4,#0CH			; skip DBPTR, DPTR and DW
	JMP	CC_UC, INIT		; continue with next initialization
@ENDI
INIT_END:				;


					; C166_BSS
@IF( @EQS(@MODEL,"MEDIUM") | @EQS(@MODEL,"LARGE") | @EQS(@MODEL,"SMALL") )
	MOV	R4, #POF ?C166_BSS_HEAD	; move intra-page offset address rom
					; data section C166_BSS to R4
BSS_DPP0:				;
	MOV	DPP0,#PAG ?C166_BSS_HEAD	; load data page pointer register DPP0
					; with data page of rom data C166_BSS
	NOP				; delay for pipeline effect
@ENDI
@IF( @EQS( @MODEL, "TINY" ) )
	MOV	R4, #?C166_BSS_HEAD	; move intra-segment offset address rom
					; data section C166_BSS to R4
@ENDI
BSS:					;
	MOV	R5, [R4+]		; BSS block header code -> R5
@IF( @EQS(@MODEL,"TINY") | @EQS(@MODEL,"SMALL") )
	CMP	R5, #05H		; check if header code 5 (near)
    @IF( @EQS(@MODEL,"SMALL") )
	JMP	CC_EQ, BSS_05		;
    @ELSE
	JMP	CC_NE, BSS_END		; if(no header code) end initialization
    @ENDI
@ENDI
@IF( @EQS(@MODEL,"MEDIUM") | @EQS(@MODEL,"LARGE") | @EQS(@MODEL,"SMALL") )
	CMP	R5, #06H		; check if header code 6 (far)
	JMP	CC_EQ, BSS_06		;
	CMP	R5, #07H		; check if header code 7 (huge)
	JMP	CC_NE, BSS_END		; if(no header code) end initialization

BSS_07:					; clear huge ram data (data > 64 K)
	MOV	SOF_RAM, [R4+]		; move intra-segment offset address ram
					; data block to SOF_RAM=R1
	MOV	R3, [R4+]		; move segment address ram data block
					; to R3
					; process data page number ram data 
	MOV	RH3, SOF_RAM_H		; R3.15:14=lower order bits of data page
	ROL	R3, #2			; R3.3:2:1:0 = data page number
	AND	R3, #0FH		; clr bit R3.15 - R3.4
	MOV	DPP1, R3		; load data page pointer register DPP1
					; with data page of ram data block
	BFLDH	SOF_RAM, #0C0H, #040H	; DPP1:POF_RAM ->SOF_RAM=R1
					;
	MOV	R5, [R4+]		; number of bytes (R6:R5) to clear in
	MOV	R6, [R4+]		; specified ram data block. 
					; MSW=R6, LSW=R5 (long word)
					;
CB07_2:	CMPD1	R5, #0			; test if all bytes are cleared and
	JMP	CC_NE, CB07_1 		; decrement number of bytes to clear.
	CMPD1	R6, #0			;
@IF( @EQS( @MODEL, "SMALL" ) )
	JMP	CC_EQ, CB07_3		;
@ELSE
	JMP	CC_EQ, BSS		; if( block end ) next initialization
@ENDI
CB07_1:	MOVB	[SOF_RAM], ZEROS	; clear byte
	CMPI1	SOF_RAM, #07FFFH	; test end of data page and inc SOF_RAM
	JMP	CC_NE, CB07_2		; if(no page end) next byte clear
	MOV	SOF_RAM, #04000H	; preset offset address ram data
	ADD	DPP1, #1		; next page ram data; increment DPP1
	JMP	CC_UC, CB07_2		; jump for next byte clear
@IF( @EQS( @MODEL, "SMALL" ) )
CB07_3:	MOV 	DPP1, #PAG ?BASE_DPP1	; restore data page register DPP1.
	JMP	CC_UC, BSS		; next initialization
@ENDI

BSS_06:					; clear far ram data. (CPU mode is
					; segmented with DPP usage linear or
					; paged.)
	MOV	POF_RAM, [R4+]		; move intra-page offset address ram
					; data block to POF_RAM=R1
	BFLDH	SOF_RAM, #0C0H, #040H	; DPP1:POF_RAM ->SOF_RAM=R1
	MOV	DPP1, [R4]		; load data page pointer register DPP1
					; with data page of ram data block
	ADD	R4, #2			; inc offset address to ram data section
					; C166_BSS and also insure a delay for 
					; pipeline effect. (DPP1 set)
					;
	MOV	R5, [R4+]		; number of bytes to clear in specified
					; ram data block
					;
CB06_1:	CMPD1	R5, #0			; test on data block end
@IF( @EQS( @MODEL, "SMALL" ) )
	JMP	CC_EQ, CB06_2 		;
@ELSE
	JMP	CC_EQ, BSS		; if( block end ) next initialization
@ENDI
	MOVB	[SOF_RAM], ZEROS	; clear byte
	ADD	SOF_RAM, #1		; inc SOF_RAM
	JMP	CC_UC, CB06_1		; jump for next byte clear
@IF( @EQS( @MODEL, "SMALL" ) )
CB06_2:	MOV 	DPP1, #PAG ?BASE_DPP1	; restore data page register DPP1
	JMP	CC_UC, BSS		; next initialization
@ENDI
@ENDI

@IF( @EQS(@MODEL,"TINY") | @EQS(@MODEL,"SMALL") )
BSS_05:					; clear near ram data. (DPP usage
					; is linear, CPU mode is segmented
					; for SMALL memory model and not
					; segmented for TINY memory model.)
	MOV	SOF_RAM, [R4+]		; move intra-segment offset address ram
					; data block to SOF_RAM=R1
					;
	MOV	R5, [R4+]		; number of bytes to clear in specified
					; ram data block
@IF( @EQS( @MODEL, "SMALL" ) )
	MOV	DPP0, #PAG ?BASE_DPP0	; restore DPP0 to its default value
@ENDI
CB05_1:	CMPD1	R5, #0			; test on data block end, and delay for
					; pipeline effect if DPP0 is restored
					; for SMALL memory model
@IF( @EQS( @MODEL, "TINY" ) )
	JMP	CC_EQ, BSS 		; if( block end ) next initialization
@ELSE
	JMP	CC_EQ, BSS_DPP0		; if( block end ) reload data page
					; pointer register DPP0 with data page
					; of rom data C166_BSS and start next
					; initialization
@ENDI
	MOVB	[SOF_RAM], ZEROS	; clear byte
	ADD	SOF_RAM, #1		; inc SOF_RAM
	JMP	CC_UC, CB05_1		; jump for next byte clear
@ENDI
BSS_END:

@IF( @EQS(@MODEL,"SMALL") )
	MOV	DPP0, #PAG ?BASE_DPP0	; restore DPP0 to its default value
@ENDI

@IF( @EQS(@MODEL,"MEDIUM") | @EQS(@MODEL,"LARGE") )
    	MOV 	DPP0, #0		 ; restore DPP0 to its default value
	MOV	DPP1, #PAG ?USRSTACK_TOP ; set DPP1 to page of user stack
	MOV	DPP2, #PAG C166_DGROUP	 ; set DPP2 to page of default data 
					 ; group
	NOP				 ; delay for pipeline effect
@ENDI

@IF( @EQS(@MODEL,"MEDIUM") | @EQS(@MODEL,"LARGE") )
	MOV	R0, #POF ?USRSTACK_TOP	; set user stack pointer
	BSET	R0.0EH			; User stack uses DPP1
@ELSE
	MOV	R0, #?USRSTACK_TOP	; set user stack pointer
@ENDI

@IF( @EVA )
	BSET	IEN			; allow monitor to break application
@ENDI

	MOV	R12, #0			; set argc to 0
	MOV	R13, #0			;
	MOV	R14, #0			; set argv[] to 0
@IF( @PXROS )
@IF( @EQS( @MODEL, "SMALL" ) | @EQS( @MODEL, "LARGE" ) )
	MOV	R1, #SOF __MAIN_RET	; store inter-segment jump to label
	MOV	[-R0], R1		; __MAIN_RET on the user stack
	MOV	R1, #SEG __MAIN_RET	;
	MOV	[-R0], R1		;
	JMPS	SEG _main, SOF _main	; call reset task main()
__MAIN_RET:				;
	ADD	R0, #4			;
@ELSE
	MOV	R1, #SOF __MAIN_RET	; store intra-segment address return
	MOV	[-R0], R1		; label __MAIN_RET on the user stack
	JMPA	CC_UC, _main		; call reset task main()
__MAIN_RET:				;
@ENDI
@ELSE
	CALL	_main			; call reset task main()
@ENDI

@IF( @EX_AB )
	MOV	R12, #0			; set exit status 0
	JMP	_exit			; jump to exit(0) function
@ENDI
; The exit() function causes normal program termination to occur. First, all 
; functions registered by the atexit() function are called in the reverse 
; order. Next, all open streams with unwritten buffered data are flushed, all 
; open streams are closed and all files created by the tmpfile() function are 
; removed. The status value passed to exit is returned in R4.
__EXIT: LABEL FAR			; the exit() or abort() function jumps
					; to this entry.
@IF( @EX_AB )
					; restore (host) environment.
	MOV	SP, #?SYSSTACK_TOP	; restore stack pointer.
@IF( @EQS(@MODEL,"MEDIUM") | @EQS(@MODEL,"LARGE") )
	MOV	R0, #POF ?USRSTACK_TOP	; restore user stack pointer
	BSET	R0.0EH			; User stack uses DPP1
@ELSE
	MOV	R0, #?USRSTACK_TOP	; restore user stack pointer
@ENDI
@IF( @FLOAT )
	MOV	R1, #?FPSTKUN		; restore floating point stack pointer.
	MOV	?FPSP, R1		; ?FPSP normally initialized via 
					; C166_INIT.
@ENDI	
@ENDI

__IDLE: IDLE				; Power down CPU until peripheral inter-
					; rupt or external interrupt occurs.
	JMPR	CC_UC, __IDLE		; set idle mode again.
	RETV				; Virtual return.
__CSTART	ENDP
__CSTART_PR	ENDS

@IF( @EQS(@MODEL,"TINY") | @EQS(@MODEL,"SMALL") )
C166_US	SECTION	LDAT WORD GLBUSRSTACK 'CUSTACK'
@ENDI
@IF( @EQS(@MODEL,"MEDIUM") | @EQS(@MODEL,"LARGE") )
C166_US	SECTION	DATA WORD GLBUSRSTACK 'CUSTACK'
@ENDI
@IF( @PXROS & ( @EQS(@MODEL,"SMALL") | @EQS(@MODEL,"LARGE") ) )
@IF( @EQS( @MODEL, "SMALL" ) | @EQS( @MODEL, "LARGE" ) )
	DS	2+4		; Allocate a user stack of at least 2 bytes +
				; return label main (__MAIN_RET).
@ELSE
	DS	2+2		; Allocate a user stack of at least 2 bytes +
				; return label main (__MAIN_RET).
@ENDI
@ELSE
	DS	2		; Allocate a user stack of at least 2 bytes
@ENDI
C166_US	ENDS

@IF( @EQS(@MODEL,"MEDIUM") | @EQS(@MODEL,"LARGE") )
C166_DGROUP	DGROUP	__DUMMY
__DUMMY	SECTION DATA WORD PUBLIC 'CNEAR'
__DUMMY	ENDS
@ENDI

;     	REGDEF R0-R15  COMMON=REGS      ; register usage      ####2####
;        EXTERN osek_sys_rb:WORD         ;                     ####2####
osek_sys_rb REGDEF R0-R15
	SSKDEF	__STKSZ			; System stack size
	
	END