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Diffstat (limited to 'src/devices/cpu/hmcs40/hmcs40d.cpp')
-rw-r--r--src/devices/cpu/hmcs40/hmcs40d.cpp66
1 files changed, 28 insertions, 38 deletions
diff --git a/src/devices/cpu/hmcs40/hmcs40d.cpp b/src/devices/cpu/hmcs40/hmcs40d.cpp
index 96e4b6399ea..d845b7545ae 100644
--- a/src/devices/cpu/hmcs40/hmcs40d.cpp
+++ b/src/devices/cpu/hmcs40/hmcs40d.cpp
@@ -11,6 +11,33 @@
#include "emu.h"
#include "hmcs40d.h"
+// constructor
+
+hmcs40_disassembler::hmcs40_disassembler()
+{
+ // init lfsr pc lut
+ for (u32 i = 0, pc = 0; i < 0x40; i++)
+ {
+ m_l2r[i] = pc;
+ m_r2l[pc] = i;
+
+ // see hmcs40_cpu_device::increment_pc()
+ u32 mask = 0x3f;
+ u32 low = pc & mask;
+ u32 fb = (low << 1 & 0x20) == (low & 0x20);
+
+ if (low == (mask >> 1))
+ fb = 1;
+ else if (low == mask)
+ fb = 0;
+
+ pc = (pc & ~mask) | ((pc << 1 | fb) & mask);
+ }
+}
+
+
+// common lookup tables
+
const char *const hmcs40_disassembler::s_mnemonics[] =
{
"?",
@@ -152,6 +179,7 @@ const u8 hmcs40_disassembler::hmcs40_mnemonic[0x400] =
};
+// disasm
offs_t hmcs40_disassembler::disassemble(std::ostream &stream, offs_t pc, const data_buffer &opcodes, const data_buffer &params)
{
@@ -197,41 +225,3 @@ offs_t hmcs40_disassembler::disassemble(std::ostream &stream, offs_t pc, const d
return 1 | s_flags[instr] | SUPPORTED;
}
-
-u32 hmcs40_disassembler::opcode_alignment() const
-{
- return 1;
-}
-
-u32 hmcs40_disassembler::interface_flags() const
-{
- return NONLINEAR_PC | PAGED;
-}
-
-u32 hmcs40_disassembler::page_address_bits() const
-{
- return 6;
-}
-
-offs_t hmcs40_disassembler::pc_linear_to_real(offs_t pc) const
-{
- static const u8 l2r[64] = {
- 0x00, 0x01, 0x03, 0x07, 0x0f, 0x1f, 0x3f, 0x3e, 0x3d, 0x3b, 0x37, 0x2f, 0x1e, 0x3c, 0x39, 0x33,
- 0x27, 0x0e, 0x1d, 0x3a, 0x35, 0x2b, 0x16, 0x2c, 0x18, 0x30, 0x21, 0x02, 0x05, 0x0b, 0x17, 0x2e,
- 0x1c, 0x38, 0x31, 0x23, 0x06, 0x0d, 0x1b, 0x36, 0x2d, 0x1a, 0x34, 0x29, 0x12, 0x24, 0x08, 0x11,
- 0x22, 0x04, 0x09, 0x13, 0x26, 0x0c, 0x19, 0x32, 0x25, 0x0a, 0x15, 0x2a, 0x14, 0x28, 0x10, 0x20,
- };
- return (pc & ~0x3f) | l2r[pc & 0x3f];
-}
-
-offs_t hmcs40_disassembler::pc_real_to_linear(offs_t pc) const
-{
- static const u8 r2l[64] = {
- 0x00, 0x01, 0x1b, 0x02, 0x31, 0x1c, 0x24, 0x03, 0x2e, 0x32, 0x39, 0x1d, 0x35, 0x25, 0x11, 0x04,
- 0x3e, 0x2f, 0x2c, 0x33, 0x3c, 0x3a, 0x16, 0x1e, 0x18, 0x36, 0x29, 0x26, 0x20, 0x12, 0x0c, 0x05,
- 0x3f, 0x1a, 0x30, 0x23, 0x2d, 0x38, 0x34, 0x10, 0x3d, 0x2b, 0x3b, 0x15, 0x17, 0x28, 0x1f, 0x0b,
- 0x19, 0x22, 0x37, 0x0f, 0x2a, 0x14, 0x27, 0x0a, 0x21, 0x0e, 0x13, 0x09, 0x0d, 0x08, 0x07, 0x06,
- };
- return (pc & ~0x3f) | r2l[pc & 0x3f];
-}
-