/*****************************************************************************
 *
 *   scops.c
 *   portable sharp 61860 emulator interface
 *   (sharp pocket computers)
 *
 *   Copyright (c) 2000 Peter Trauner, all rights reserved.
 *
 *   - This source code is released as freeware for non-commercial purposes.
 *   - You are free to use and redistribute this code in modified or
 *     unmodified form, provided you list me in the credits.
 *   - If you modify this source code, you must add a notice to each modified
 *     source file that it has been changed.  If you're a nice person, you
 *     will clearly mark each change too.  :)
 *   - If you wish to use this for commercial purposes, please contact me at
 *     peter.trauner@jk.uni-linz.ac.at
 *   - The author of this copywritten work reserves the right to change the
 *     terms of its usage and license at any time, including retroactively
 *   - This entire notice must remain in the source code.
 *
 * History of changes:
 * 21.07.2001 Several changes listed below were made by Mario Konegger
 *            (konegger@itp.tu-graz.ac.at)
 *        replaced buggy BCD-commands add_bcd, sub_bcd, add_bcd_a,
 *            sub_bcd_a and changed out_c, to implement HLT-mode of the CPU.
 *
 *****************************************************************************/

INLINE UINT8 READ_OP(void)
{
	return cpu_readop(sc61860.pc++);
}

INLINE UINT8 READ_OP_ARG(void)
{
	return cpu_readop_arg(sc61860.pc++);
}

INLINE UINT16 READ_OP_ARG_WORD(void)
{
	UINT16 t=cpu_readop(sc61860.pc++)<<8;
	t|=cpu_readop(sc61860.pc++);
	return t;
}

INLINE UINT8 READ_BYTE(UINT16 adr)
{
	return program_read_byte(adr);
}

INLINE void WRITE_BYTE(UINT16 a,UINT8 v)
{
	program_write_byte(a,v);
}

#define PUSH(v) sc61860.ram[--sc61860.r]=v
#define POP() sc61860.ram[sc61860.r++]

INLINE void sc61860_load_imm(int r, UINT8 v)
{
	sc61860.ram[r]=v;
}

INLINE void sc61860_load(void)
{
	sc61860.ram[A]=sc61860.ram[sc61860.p];
}

INLINE void sc61860_load_imm_p(UINT8 v)
{
	sc61860.p=v&0x7f;
}

INLINE void sc61860_load_imm_q(UINT8 v)
{
	sc61860.q=v&0x7f;
}

INLINE void sc61860_load_r(void)
{
	sc61860.r=sc61860.ram[A]&0x7f;
}

INLINE void sc61860_load_ext(int r)
{
	sc61860.ram[r]=READ_BYTE(sc61860.dp);
}

INLINE void sc61860_load_dp(void)
{
	sc61860.dp=READ_OP_ARG_WORD();
}

INLINE void sc61860_load_dl(void)
{
	sc61860.dp=(sc61860.dp&~0xff)|READ_OP_ARG();
}

INLINE void sc61860_store_p(void)
{
	sc61860.ram[A]=sc61860.p;
}

INLINE void sc61860_store_q(void)
{
	sc61860.ram[A]=sc61860.q;
}

INLINE void sc61860_store_r(void)
{
	sc61860.ram[A]=sc61860.r;
}

INLINE void sc61860_store_ext(int r)
{
	WRITE_BYTE(sc61860.dp, sc61860.ram[r]);
}

INLINE void sc61860_exam(int a, int b)
{
	UINT8 t=sc61860.ram[a];
	sc61860.ram[a]=sc61860.ram[b];
	sc61860.ram[b]=t;
}

INLINE void sc61860_test(int reg, UINT8 value)
{
	sc61860.zero=(sc61860.ram[reg]&value)==0;
}

INLINE void sc61860_test_ext(void)
{
	sc61860.zero=(READ_BYTE(sc61860.dp)&READ_OP_ARG())==0;
}

INLINE void sc61860_and(int reg, UINT8 value)
{
	sc61860.zero=(sc61860.ram[reg]&=value)==0;
}

INLINE void sc61860_and_ext(void)
{
	UINT8 t=READ_BYTE(sc61860.dp)&READ_OP_ARG();
	sc61860.zero=t==0;
    WRITE_BYTE(sc61860.dp,t);
}

INLINE void sc61860_or(int reg, UINT8 value)
{
	sc61860.zero=(sc61860.ram[reg]|=value)==0;
}

INLINE void sc61860_or_ext(void)
{
	UINT8 t=READ_BYTE(sc61860.dp)|READ_OP_ARG();
	sc61860.zero=t==0;
    WRITE_BYTE(sc61860.dp,t);
}

INLINE void sc61860_rotate_right(void)
{
	int t=sc61860.ram[A];
	if (sc61860.carry) t|=0x100;
	sc61860.carry=t&1;
	sc61860.ram[A]=t>>1;
}

INLINE void sc61860_rotate_left(void)
{
	int t=sc61860.ram[A]<<1;
	if (sc61860.carry) t|=1;
	sc61860.carry=t&0x100;
	sc61860.ram[A]=t;
}

INLINE void sc61860_swap(void)
{
	int t=sc61860.ram[A];
	sc61860.ram[A]=(t<<4)|((t>>4)&0xf);
}

// q=reg sideeffect
INLINE void sc61860_inc(int reg)
{
	sc61860.q=reg;
	sc61860.ram[reg]++;
	sc61860.zero=sc61860.carry=sc61860.ram[reg]==0;
}

INLINE void sc61860_inc_p(void)
{
	sc61860.p++;
}

// q=reg sideeffect
INLINE void sc61860_dec(int reg)
{
	sc61860.q=reg;
	sc61860.ram[reg]--;
	sc61860.zero=sc61860.ram[reg]==0;
	sc61860.carry=sc61860.ram[reg]==0xff;
}

INLINE void sc61860_dec_p(void)
{
	sc61860.p--;
}

INLINE void sc61860_add(int reg, UINT8 value)
{
	int t=sc61860.ram[reg]+value;
	sc61860.zero=(sc61860.ram[reg]=t)==0;
	sc61860.carry=t>=0x100;
}

INLINE void sc61860_add_carry(void)
{
	int t=sc61860.ram[sc61860.p]+sc61860.ram[A];
	if (sc61860.carry) t++;
	sc61860.zero=(sc61860.ram[sc61860.p]=t)==0;
	sc61860.carry=t>=0x100;
}

// p++ sideeffect
INLINE void sc61860_add_word(void)
{
	int t=sc61860.ram[sc61860.p]+sc61860.ram[A],t2;
	sc61860.ram[sc61860.p]=t;
	sc61860.p++;
	t2=sc61860.ram[sc61860.p]+sc61860.ram[B];
	if (t>=0x100) t2++;
	sc61860.ram[sc61860.p]=t2;
	sc61860.zero=(t2&0xff)==0 &&(t&0xff)==0;
	sc61860.carry=t2>=0x100;
}


INLINE void sc61860_sub(int reg, UINT8 value)
{
	int t=sc61860.ram[reg]-value;
	sc61860.zero=(sc61860.ram[reg]=t)==0;
	sc61860.carry=t<0;
}

INLINE void sc61860_sub_carry(void)
{
	int t=sc61860.ram[sc61860.p]-sc61860.ram[A];
	if (sc61860.carry) t--;
	sc61860.zero=(sc61860.ram[sc61860.p]=t)==0;
	sc61860.carry=t<0;
}


// p++ sideeffect
INLINE void sc61860_sub_word(void)
{
	int t=sc61860.ram[sc61860.p]-sc61860.ram[A],t2;
	sc61860.ram[sc61860.p]=t;
	sc61860.p++;
	t2=sc61860.ram[sc61860.p]-sc61860.ram[B];
	if (t<0) t2--;
	sc61860.ram[sc61860.p]=t2;
	sc61860.zero=(t2&0xff)==0 && (t&0xff)==0;
	sc61860.carry=t2<0;
}

INLINE void sc61860_cmp(int reg, UINT8 value)
{
	int t=sc61860.ram[reg]-value;
	sc61860.zero=t==0;
	sc61860.carry=t<0;
}

INLINE void sc61860_pop(void)
{
	sc61860.ram[A]=POP();
}

INLINE void sc61860_push(void)
{
	PUSH(sc61860.ram[A]);
}

INLINE void sc61860_prepare_table_call(void)
{
	int adr;
	sc61860.h=READ_OP();
	adr=READ_OP_ARG_WORD();
	PUSH(adr>>8);
	PUSH(adr&0xff);
}

INLINE void sc61860_execute_table_call(void)
{
	int i, v, adr;
	for (i=0; i<sc61860.h; i++) {
		v=READ_OP();
		adr=READ_OP_ARG_WORD();
		sc61860.zero=v==sc61860.ram[A];
		if (sc61860.zero) {
			sc61860.pc=adr;
			change_pc(sc61860.pc);
			return;
		}
	}
	sc61860.pc=READ_OP_ARG_WORD();
	change_pc(sc61860.pc);
}


INLINE void sc61860_call(UINT16 adr)
{
	PUSH(sc61860.pc>>8);
	PUSH(sc61860.pc&0xff);
	sc61860.pc=adr;
	change_pc(sc61860.pc);
}

INLINE void sc61860_return(void)
{
	UINT16 t=POP();
	t|=POP()<<8;
	sc61860.pc=t;
	change_pc(sc61860.pc);
}

INLINE void sc61860_jump(int yes)
{
	UINT16 adr=READ_OP_ARG_WORD();
	if (yes) {
		sc61860.pc=adr;
		change_pc(sc61860.pc);
	}
}

INLINE void sc61860_jump_rel_plus(int yes)
{
	UINT16 adr=sc61860.pc;
	adr+=READ_OP_ARG();
	if (yes) {
		sc61860.pc=adr;
		change_pc(sc61860.pc);
		sc61860_ICount-=3;
	}
}

INLINE void sc61860_jump_rel_minus(int yes)
{
	UINT16 adr=sc61860.pc;
	adr-=READ_OP_ARG();
	if (yes) {
		sc61860.pc=adr;
		change_pc(sc61860.pc);
		sc61860_ICount-=3;
	}
}

INLINE void sc61860_loop(void)
{
	UINT16 adr=sc61860.pc;
	adr-=READ_OP_ARG();
	sc61860.ram[sc61860.r]--;
	sc61860.zero=sc61860.ram[sc61860.r]==0;
	sc61860.carry=sc61860.ram[sc61860.r]==0xff;
	if (!sc61860.carry) {
		sc61860.pc=adr;
		adr=POP();
		change_pc(sc61860.pc);
		sc61860_ICount-=3;
	}
}

INLINE void sc61860_leave(void)
{
	sc61860.ram[sc61860.r]=0;
}

INLINE void sc61860_wait(void)
{
	int t=READ_OP();
	sc61860_ICount-=t;
	sc61860_ICount-=t;
	sc61860_ICount-=3;
}

INLINE void sc61860_set_carry(void)
{
	sc61860.carry=1;
	sc61860.zero=1;
}

INLINE void sc61860_reset_carry(void)
{
	sc61860.carry=0;
	sc61860.zero=1;
}

INLINE void sc61860_out_a(void)
{
	sc61860.q=IA;
	if (sc61860.config&&sc61860.config->outa)
	    sc61860.config->outa(sc61860.ram[IA]);
}

INLINE void sc61860_out_b(void)
{
	sc61860.q=IB;
	if (sc61860.config&&sc61860.config->outb)
	    sc61860.config->outb(sc61860.ram[IB]);
}

INLINE void sc61860_out_f(void)
{
	sc61860.q=F0;
	/*sc61860.ram[F0]; */
}


/*   c0 display on
   c1 counter reset
   c2 cpu halt
   c3 computer off
   c4 beeper frequency (1 4khz, 0 2khz), or (c5=0) membran pos1/pos2
   c5 beeper on
   c6 beeper steuerung*/
INLINE void sc61860_out_c(void)
{
    sc61860.q=C;
    if (sc61860.config&&sc61860.config->outc)
	sc61860.config->outc(sc61860.ram[C]);
    sc61860.c=sc61860.ram[C];
}

INLINE void sc61860_in_a(void)
{
	int data=0;
	if (sc61860.config&&sc61860.config->ina) data=sc61860.config->ina();
	sc61860.ram[A]=data;
	sc61860.zero=data==0;
}

INLINE void sc61860_in_b(void)
{
	int data=0;
	if (sc61860.config&&sc61860.config->inb) data=sc61860.config->inb();
	sc61860.ram[A]=data;
	sc61860.zero=data==0;
}

/* 0 systemclock 512ms
   1 systemclock 2ms
   2 ?
   3 brk/on key
   4 ?
   5 ?
   6 reset
   7 cassette input */
INLINE void sc61860_test_special(void)
{
	int t=0;
	if (sc61860.timer.t512ms) t|=1;
	if (sc61860.timer.t2ms) t|=2;
	if (sc61860.config&&sc61860.config->brk&&sc61860.config->brk()) t|=8;
	if (sc61860.config&&sc61860.config->reset&&sc61860.config->reset()) t|=0x40;
	if (sc61860.config&&sc61860.config->x&&sc61860.config->x()) t|=0x80;

	sc61860.zero=(t&READ_OP())==0;
}

/************************************************************************************
 "string" operations
***********************************************************************************/

// p-=I+1 sideeffect
INLINE void sc61860_add_bcd_a(void)
{
 UINT8 help = sc61860.ram[A];
 int i, hlp, hlp1 = 0; sc61860.zero=1;
 for ( i=0; i <= sc61860.ram[I]; i++)
 {
  hlp1 = (sc61860.ram[sc61860.p] & 0x0f) + (help & 0x0f ) + hlp1;
  if (hlp1 > 9) { hlp = hlp1 - 0x0a; hlp1 = 0x10; }
  else {hlp = hlp1; hlp1 = 0x00;}
  hlp1 = (sc61860.ram[sc61860.p] & 0xf0) + (help & 0xf0) + hlp1;
  if (hlp1 > 0x90) { sc61860.ram[sc61860.p] = hlp1 - 0xa0 + hlp; hlp1 = 1; }
  else {sc61860.ram[sc61860.p] = hlp1 + hlp; hlp1 = 0;}
  if ( sc61860.ram[sc61860.p--] != 0 ) sc61860.zero = 0;
  help = 0;
 }
 sc61860.carry= ( hlp1 ) ? 1 : 0;
 sc61860_ICount-=3*(sc61860.ram[I]+1);
}


// p-=I+1, q-=I+2 sideeffect
INLINE void sc61860_add_bcd(void)
{
 int i, hlp, hlp1 = 0; sc61860.zero=1;
 for ( i=0; i <= sc61860.ram[I]; i++)
 {
  hlp1 = (sc61860.ram[sc61860.p] & 0x0f) + (sc61860.ram[sc61860.q] & 0x0f ) +
hlp1;
  if (hlp1 > 9) { hlp = hlp1 - 0x0a; hlp1 = 0x10; }
  else {hlp = hlp1; hlp1 = 0x00;}
  hlp1 = (sc61860.ram[sc61860.p] & 0xf0) + (sc61860.ram[sc61860.q--] & 0xf0) +
hlp1;
  if (hlp1 > 0x90) { sc61860.ram[sc61860.p] = hlp1 - 0xa0 + hlp; hlp1 = 1; }
  else {sc61860.ram[sc61860.p] = hlp1 + hlp; hlp1 = 0;}
  if ( sc61860.ram[sc61860.p--] != 0 ) sc61860.zero = 0;
 }
 sc61860.carry= ( hlp1 ) ? 1 : 0;
 sc61860_ICount-=3*(sc61860.ram[I]+1);
 sc61860.q--;
}


// p-=I+1 sideeffect
INLINE void sc61860_sub_bcd_a(void)
{
 UINT8 help = sc61860.ram[A];
 int i, hlp, hlp1 = 0; sc61860.zero=1;
 for ( i=0; i <= sc61860.ram[I]; i++)
 {
  hlp1 = (sc61860.ram[sc61860.p]&0x0f) - (help&0x0f) - hlp1;
  if ( hlp1 < 0 ) { hlp = hlp1 + 0x0a; hlp1 = 0x10;}
  else { hlp = hlp1; hlp1 = 0x00;}
  hlp1 = (sc61860.ram[sc61860.p]&0xf0) - (help&0xf0) - hlp1;
  if ( hlp1 < 0 ) { sc61860.ram[sc61860.p] = hlp1 + 0xa0 + hlp; hlp1 = 1;}
  else {sc61860.ram[sc61860.p] = hlp1 + hlp; hlp1 = 0;}
  if ( sc61860.ram[sc61860.p--] != 0 ) sc61860.zero = 0;
  help = 0;
 }
 sc61860.carry= ( hlp1 ) ? 1 : 0;
 sc61860_ICount-=3*(sc61860.ram[I]+1);
}


// p-=I+1, q-=I+2 sideeffect
INLINE void sc61860_sub_bcd(void)
{
 int i, hlp, hlp1 = 0; sc61860.zero=1;
 for ( i=0; i <= sc61860.ram[I]; i++)
 {
  hlp1 = (sc61860.ram[sc61860.p]&0x0f) - (sc61860.ram[sc61860.q]&0x0f) - hlp1;
  if ( hlp1 < 0 ) { hlp = hlp1 + 0x0a; hlp1 = 0x10;}
  else { hlp = hlp1; hlp1 = 0x00;}
  hlp1 = (sc61860.ram[sc61860.p]&0xf0) - (sc61860.ram[sc61860.q--]&0xf0) -
hlp1;
  if ( hlp1 < 0 ) { sc61860.ram[sc61860.p] = hlp1 + 0xa0 + hlp; hlp1 = 1;}
  else {sc61860.ram[sc61860.p] = hlp1 + hlp; hlp1 = 0;}
  if ( sc61860.ram[sc61860.p--] != 0 ) sc61860.zero = 0;
 }
 sc61860.carry= ( hlp1 ) ? 1 : 0;
 sc61860_ICount-=3*(sc61860.ram[I]+1);
 sc61860.q--;
}

/* side effect p-i-1 -> p correct! */
INLINE void sc61860_shift_left_nibble(void)
{
	int i,t=0;
	for (i=0; i<=sc61860.ram[I]; i++) {
		t|=sc61860.ram[sc61860.p]<<4;
		sc61860.ram[sc61860.p--]=t;
		t>>=8;
		sc61860_ICount--;
	}
}

/* side effect p+i+1 -> p correct! */
INLINE void sc61860_shift_right_nibble(void)
{
	int i,t=0;
	for (i=0; i<=sc61860.ram[I]; i++) {
		t|=sc61860.ram[sc61860.p];
		sc61860.ram[sc61860.p++]=t>>4;
		t=(t<<8)&0xf00;
		sc61860_ICount--;
	}
}

// q=reg+1 sideeffect
INLINE void sc61860_inc_load_dp(int reg)
{
    if (++sc61860.ram[reg]==0) sc61860.ram[reg+1]++;
    sc61860.dp=sc61860.ram[reg]|(sc61860.ram[reg+1]<<8);
    sc61860.q=reg+1;
}

// q=reg+1 sideeffect
INLINE void sc61860_dec_load_dp(int reg)
{
    if (--sc61860.ram[reg]==0xff) sc61860.ram[reg+1]--;
    sc61860.dp=sc61860.ram[reg]|(sc61860.ram[reg+1]<<8);
    sc61860.q=reg+1;
}

// q=XH sideeffect
INLINE void sc61860_inc_load_dp_load(void)
{
    if (++sc61860.ram[XL]==0) sc61860.ram[XH]++;
    sc61860.dp=sc61860.ram[XL]|(sc61860.ram[XH]<<8);
    sc61860.q=XH; // hopefully correct before real read
    sc61860.ram[A]=READ_BYTE(sc61860.dp);
}

// q=XH sideeffect
INLINE void sc61860_dec_load_dp_load(void)
{
    if (--sc61860.ram[XL]==0xff) sc61860.ram[XH]--;
    sc61860.dp=sc61860.ram[XL]|(sc61860.ram[XH]<<8);
    sc61860.q=XH; // hopefully correct before real read
    sc61860.ram[A]=READ_BYTE(sc61860.dp);
}

// q=YH sideeffect
INLINE void sc61860_inc_load_dp_store(void)
{
    if (++sc61860.ram[YL]==0) sc61860.ram[YH]++;
    sc61860.dp=sc61860.ram[YL]|(sc61860.ram[YH]<<8);
    sc61860.q=YH; // hopefully correct before real write!
    WRITE_BYTE(sc61860.dp,sc61860.ram[A]);
}

// q=YH sideeffect
INLINE void sc61860_dec_load_dp_store(void)
{
    if (--sc61860.ram[YL]==0xff) sc61860.ram[YH]--;
    sc61860.dp=sc61860.ram[YL]|(sc61860.ram[YH]<<8);
    sc61860.q=XH; // hopefully correct before real write!
    WRITE_BYTE(sc61860.dp,sc61860.ram[A]);
}

INLINE void sc61860_fill(void)
{
	int i;
	for (i=0;i<=sc61860.ram[I];i++) {
		sc61860.ram[sc61860.p++]=sc61860.ram[A]; /* could be overwritten? */
		sc61860_ICount--;
	}
}

INLINE void sc61860_fill_ext(void)
{
	int i;
	for (i=0;i<=sc61860.ram[I];i++) {
		WRITE_BYTE(sc61860.dp, sc61860.ram[A]);
		if (i!=sc61860.ram[I]) sc61860.dp++;
		sc61860_ICount-=3;
	}
}

// p+=count+1, q+=count+1 sideeffects
INLINE void sc61860_copy(int count)
{
	int i;
	for (i=0; i<=count; i++) {
		sc61860.ram[sc61860.p++]=sc61860.ram[sc61860.q++];
		sc61860_ICount-=2;
	}

}

// p+=count+1, dp+=count sideeffects
INLINE void sc61860_copy_ext(int count)
{
	int i;
	for (i=0; i<=count; i++) {
		sc61860.ram[sc61860.p++]=READ_BYTE(sc61860.dp);
		if (i!=count) sc61860.dp++;
		sc61860_ICount-=4;
	}
}

INLINE void sc61860_copy_int(int count)
{
	int i;
	for (i=0; i<=count; i++) {
		sc61860.ram[sc61860.p++]=
			READ_BYTE((sc61860.ram[A]|(sc61860.ram[B]<<8)) ); /* internal rom! */
		if (i!=count) {
			if (++sc61860.ram[A]==0) sc61860.ram[B]++;
		}
		sc61860_ICount-=4;
	}
}

INLINE void sc61860_exchange(int count)
{
	int i;
	UINT8 t;
	for (i=0; i<=count; i++) {
		t=sc61860.ram[sc61860.p];
		sc61860.ram[sc61860.p++]=sc61860.ram[sc61860.q];
		sc61860.ram[sc61860.q++]=t;
		sc61860_ICount-=3;
	}
}

INLINE void sc61860_exchange_ext(int count)
{
	int i;
	UINT8 t;
	for (i=0; i<=count; i++) {
		t=sc61860.ram[sc61860.p];
		sc61860.ram[sc61860.p++]=READ_BYTE(sc61860.dp);
		WRITE_BYTE(sc61860.dp, t);
		if (i!=count) sc61860.dp++;
		sc61860_ICount-=6;
	}
}

// undocumented
// only 1 opcode working in pc1403
// both opcodes working in pc1350
INLINE void sc61860_wait_x(int level)
{
    int c;
    sc61860.zero=level;

    if (sc61860.config&&sc61860.config->x) {
	for (c=sc61860.ram[I]; c>=0; c--) {
//      sc61860.ram[sc61860.p]=(sc61860.ram[sc61860.p]+1)%0x60;
	    sc61860.ram[sc61860.p]=(sc61860.ram[sc61860.p]+1)&0x7f;
	    sc61860.zero=sc61860.config->x();
	    sc61860_ICount-=4;
	    if ( level != sc61860.zero) break;
	}
    }
}