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;

;	$Id: Cstartup.s01 1.24 2001/01/04 12:19:06 IPEO Exp $

;

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

;						      	   ;

;		    CSTARTUP.S01		      	   ;

;						      	   ;

; This file contains the Z80/HD64180 C startup routine     ;

; and must usually be tailored to suit customer's hardware.;

;						      	   ;

; Version:  4.00 [ 28/Apr/94 IJAR]                         ;

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

#define proc64180 ((__TID__&0x010)==0x010)

	NAME	CSTARTUP

	EXTERN	main			; where to begin execution

	EXTERN	?C_EXIT			; where to go when program is done

#ifdef banking

#if proc64180

CBAR_addr EQU	3AH	       ; define I/O ports to MMU registers

CBR_addr  EQU	38H	       ; (See also defines in debug.s01 and l08.s01)

	EXTERN  CBAR_value

	EXTERN  CBR_value

#endif

	EXTERN	?BANK_CALL_DIRECT_L08

#endif

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

;  CSTACK - The C stack segment					;

;  								;

;  Please, see in the link file lnk*.xcl how to increment	;

;  the stack size without having to reassemble cstartup.s01 !	;

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

	RSEG	CSTACK

	DEFS	0			; a bare minimum !

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

;  Forward declarations of segment used during initialization	;

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

	RSEG	UDATA0

	RSEG	IDATA0

	RSEG	ECSTR

	RSEG	TEMP

	RSEG	DATA0

	RSEG	WCSTR

	RSEG	CDATA0

	RSEG	CCSTR

	RSEG	CONST

	RSEG	CSTR

	ASEG

	ORG	0x6000

init_A

	DI

	JP	init_C

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

;  RCODE - where the execution actually begins			;

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

	RSEG	RCODE

init_C

	LD	SP,.SFE.(CSTACK-1)	; from high to low address

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

; If hardware must be initiated from assembly or if interrupts	;

; should be on when reaching main, this is the place to insert	;

; such code.							;

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

#ifdef banking

#if proc64180

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

; Setting of MMU registers - see chapter "Linking" of manual.	;

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

	LD	A,CBAR_value			; set CBAR value

	OUT0	(CBAR_addr),A

	LD	A,CBR_value			; set CBR value

	OUT0	(CBR_addr),A

#endif

#endif

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

; If it is not a requirement that static/global data is set	;

; to zero or to some explicit value at startup, the following	;

; line refering to seg_init can be deleted, or commented.	;

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

	CALL	seg_init

#ifdef banking

	LD	HL,LWRD(main)		; banked call to main()

	LD	A,BYTE3(main)

	CALL	?BANK_CALL_DIRECT_L08

#else

	CALL	main			; non-banked call to main()

#endif

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

; Now when we are ready with our C program we must perform a    ;

; system-dependent action.  In this case we just stop.		;

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

; DO NOT CHANGE THE NEXT LINE OF CSTARTUP IF YOU WANT TO RUN    ;

; YOUR SOFTWARE WITH THE HELP OF THE C-SPY HLL DEBUGGER.        ;

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

	JP	?C_EXIT	

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

; Copy initialized PROMmed code to shadow RAM and clear		;

; uninitialized variables.					;

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

seg_init

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

; Zero out UDATA0			;

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

	LD	HL,.SFE.(UDATA0)

	LD	DE,.SFB.(UDATA0)

	CALL	zero_mem

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

; Copy CDATA0 into IDATA0		;

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

	LD	DE,.SFB.(IDATA0)		;destination address

	LD	HL,.SFE.(CDATA0)

	LD	BC,.SFB.(CDATA0)

	CALL	copy_mem

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

; Copy CCSTR into ECSTR			;

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

	LD	DE,.SFB.(ECSTR)			;destination address

	LD	HL,.SFE.(CCSTR)

	LD	BC,.SFB.(CCSTR)

	; Just fall in to the copy_mem function

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

; Copy memory				;

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

copy_mem

	XOR	A

	SBC	HL,BC

	PUSH	BC

	LD	C,L

	LD	B,H				; BC - that many bytes

	POP	HL				; source address

	RET	Z				; If block size = 0 return now

	LDIR

	RET

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

; Clear memory				;

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

zero_mem

	XOR	A

again	PUSH	HL

	SBC	HL,DE

	POP	HL

	RET	Z

	LD	(DE),A

	INC	DE

	JR	again

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

; Interrupt vectors must be inserted here by the user.		;

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

	COMMON	INTVEC

	ENDMOD	init_A

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

; Function/module: exit (int code)				;

;								;

; When C-SPY is used this code will automatically be replaced   ;

; by a 'debug' version of exit().				;

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

	MODULE	exit

	PUBLIC	exit

	PUBLIC	?C_EXIT

	RSEG	RCODE

?C_EXIT

exit	EQU	?C_EXIT

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

; The next line can be replaced by user defined code.          ;

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

        NOP

	JR	$			; loop forever

	END