diff options
Diffstat (limited to 'trunk/src/emu/cpu/ssp1601/ssp1601d.c')
-rw-r--r-- | trunk/src/emu/cpu/ssp1601/ssp1601d.c | 298 |
1 files changed, 298 insertions, 0 deletions
diff --git a/trunk/src/emu/cpu/ssp1601/ssp1601d.c b/trunk/src/emu/cpu/ssp1601/ssp1601d.c new file mode 100644 index 00000000000..9952afe6db5 --- /dev/null +++ b/trunk/src/emu/cpu/ssp1601/ssp1601d.c @@ -0,0 +1,298 @@ +/* + + SSP1601 disassembler + written by Pierpaolo Prazzoli + updated for SSP1601 by Grazvydas Ignotas + +*/ + +#include "emu.h" +#include "debugger.h" + + +static const char *const reg[16] = +{ + "-", "X", "Y", "A", + "ST", "STACK", "PC", "P", + "EXT0", "EXT1", "EXT2", "EXT3", + "EXT4", "EXT5", "EXT6", "AL" +}; + +static const char *const rij[8] = +{ + "r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7" +}; + +static const char *const modifier[4] = +{ + "", "+!", "-", "+" +}; + +static const char *const modifier_sf[4] = +{ + "|00", "|01", "|10", "|11" +}; + +static const char *const cond[16] = +{ + "always", "RESERVED", "gpi0", "gpi1", + "l", "z", "ov", "n", + "diof", "gpi2", "gpi3", "RESERVED", + "RESERVED", "RESERVED", "RESERVED", "RESERVED", +}; + +static const char *const acc_op[8] = +{ + "ror", "rol", "shr", "shl", "inc", "dec", "neg", "abs" +}; + +// pag. 81 uses different addresses! +static const char *const flag_op[16] = +{ + "?", "?", "resl", "setl", "resie", "setie", "?", "?", "resop", "setop", "?", "?", "?", "?", "res", "set" +}; + +static const char *const arith_ops[8] = +{ + "", "add", "", "cmp", "add", "and", "or", "eor" +}; + + +#define BIT_B ((op >> 8) & 1) +#define RIJ rij[(BIT_B << 2) + (op & 3)] +#define RI(i) rij[(i) & 3] +#define RJ(i) rij[((i) & 3) + 4] +#define MODIFIER(mod,r3) (((r3) == 3) ? modifier_sf[mod] : modifier[mod]) +#define MODIFIER_LOW MODIFIER((op >> 2) & 3, op&3) +#define MODIFIER_HIGH MODIFIER((op >> 6) & 3, (op >> 4)&3) + +#define READ_OP_DASM(p) ((base_oprom[p] << 8) | base_oprom[(p) + 1]) + +static char *get_cond(int op) +{ + static char scond[16]; + if (op&0xf0) sprintf(scond, "%s=%i", cond[(op >> 4) & 0xf], BIT_B); + else sprintf(scond, "%s", cond[(op >> 4) & 0xf]); + return scond; +} + + +static unsigned dasm_ssp1601(char *buffer, unsigned pc, const UINT8 *oprom) +{ + const UINT8 *base_oprom; + UINT16 op; + int size = 1; + int flags = 0; + + base_oprom = oprom; + + op = READ_OP_DASM(0); + + switch (op >> 9) + { + case 0x00: + if(op == 0) + { + // nop + sprintf(buffer, "nop"); + } + else if((op & 0xff) == 0x65) + { + // ret + sprintf(buffer, "ret"); + flags |= DASMFLAG_STEP_OUT; + } + else + { + // ld d, s + sprintf(buffer, "ld %s, %s", reg[(op >> 4) & 0xf], reg[op & 0xf]); + } + break; + + // ld d, (ri) + case 0x01: + sprintf(buffer, "ld %s, (%s%s)", reg[(op >> 4) & 0xf], RIJ, MODIFIER_LOW); + break; + + // ld (ri), s + case 0x02: + sprintf(buffer, "ld (%s%s), %s", RIJ, MODIFIER_LOW, reg[(op >> 4) & 0xf]); + break; + + // ld a, addr + case 0x03: + sprintf(buffer, "ld A, %X", op & 0x1ff); + break; + + // ldi d, imm + case 0x04: + sprintf(buffer, "ld %s, %X", reg[(op >> 4) & 0xf], READ_OP_DASM(2)); + size = 2; + break; + + // ld d, ((ri)) + case 0x05: + sprintf(buffer, "ld %s, ((%s%s))", reg[(op >> 4) & 0xf], RIJ, MODIFIER_LOW); + break; + + // ldi (ri), imm + case 0x06: + sprintf(buffer, "ld (%s%s), %X", RIJ, MODIFIER_LOW, READ_OP_DASM(2)); + size = 2; + break; + + // ld addr, a + case 0x07: + sprintf(buffer, "ld %X, A", op & 0x1ff); + break; + + // ld d, ri + case 0x09: + sprintf(buffer, "ld %s, %s%s", reg[(op >> 4) & 0xf], RIJ, MODIFIER_LOW); + break; + + // ld ri, s + case 0x0a: + sprintf(buffer, "ld %s%s, %s", RIJ, MODIFIER_LOW, reg[(op >> 4) & 0xf]); + break; + + // ldi ri, simm + case 0x0c: + case 0x0d: + case 0x0e: + case 0x0f: + sprintf(buffer, "ldi %s, %X", rij[(op >> 8) & 7], op & 0xff); + break; + + // op a, s + case 0x10: + case 0x30: + case 0x40: + case 0x50: + case 0x60: + case 0x70: + sprintf(buffer, "%s A, %s", arith_ops[op >> 13], reg[op & 0xf]); + break; + + // op a, (ri) + case 0x11: + case 0x31: + case 0x41: + case 0x51: + case 0x61: + case 0x71: + sprintf(buffer, "%s A, (%s%s)", arith_ops[op >> 13], RIJ, MODIFIER_LOW); + break; + + // op a, adr + case 0x13: + case 0x33: + case 0x43: + case 0x53: + case 0x63: + case 0x73: + sprintf(buffer, "%s A, %X", arith_ops[op >> 13], op & 0x1ff); + break; + + // subi a, imm + case 0x14: + case 0x34: + case 0x44: + case 0x54: + case 0x64: + case 0x74: + sprintf(buffer, "%si A, %X", arith_ops[op >> 13], READ_OP_DASM(2)); + size = 2; + break; + + // op a, ((ri)) + case 0x15: + case 0x35: + case 0x45: + case 0x55: + case 0x65: + case 0x75: + sprintf(buffer, "%s A, ((%s%s))", arith_ops[op >> 13], RIJ, MODIFIER_LOW); + break; + + // sub a, ri + case 0x19: + case 0x39: + case 0x49: + case 0x59: + case 0x69: + case 0x79: + sprintf(buffer, "%s A, %s%s", arith_ops[op >> 13], RIJ, MODIFIER_LOW); + break; + + // mpys (rj), (ri), b + case 0x1b: + sprintf(buffer, "mpya (%s%s), (%s%s), %d", RJ(op >> 4), MODIFIER_HIGH, RI(op), MODIFIER_LOW, BIT_B); + break; + + // subi simm + case 0x1c: + case 0x3c: + case 0x4c: + case 0x5c: + case 0x6c: + case 0x7c: + sprintf(buffer, "%si %X", arith_ops[op >> 13], op & 0xff); + break; + + // call cond, addr + case 0x24: + sprintf(buffer, "call %s, %X", get_cond(op), READ_OP_DASM(2)); + flags |= DASMFLAG_STEP_OVER; + size = 2; + break; + + // ld d, (a) + case 0x25: + sprintf(buffer, "ld %s, (A)", reg[(op >> 4) & 0xf]); + break; + + // bra cond, addr + case 0x26: + sprintf(buffer, "bra %s, %X", get_cond(op), READ_OP_DASM(2)); + size = 2; + break; + + // mod cond, op + case 0x48: + sprintf(buffer, "mod %s, %s", get_cond(op), acc_op[op & 7]); + break; + + // mod f, op + case 0x4a: + sprintf(buffer, "%s", flag_op[op & 0xf]); + break; + + // mpya (rj), (ri), b + case 0x4b: + sprintf(buffer, "mpya (%s%s), (%s%s), %d", RJ(op >> 4), MODIFIER_HIGH, RI(op), MODIFIER_LOW, BIT_B); + break; + + // mld (rj), (ri), b + case 0x5b: + sprintf(buffer, "mld (%s%s), (%s%s), %d", RJ(op >> 4), MODIFIER_HIGH, RI(op), MODIFIER_LOW, BIT_B); + break; + + default: + sprintf(buffer, "OP = %04X", op); + break; + } + + return size | flags | DASMFLAG_SUPPORTED; +} + +// vim:ts=4 + +CPU_DISASSEMBLE( ssp1601 ) +{ + //ssp1601_state_t *ssp1601_state = get_safe_token(device); + + return dasm_ssp1601(buffer, pc, oprom); +} + + |