diff options
| -rw-r--r-- | main.asm | 36 |
1 files changed, 22 insertions, 14 deletions
@@ -46,36 +46,42 @@ ;; Macro to read a byte from main memory at register \1. Puts ;; the byte read in \2. -FETCHB MACRO ; 14 cycles, 4 bytes - ;; XXX deref - move.b 0(a6,\1.w),\2 +FETCHB MACRO ; XX cycles, X bytes + move.w \1,d1 + bsr deref + move.b (a0),\2 ENDM - ;; Macro to write a byte in \1 to main memory at \2 (regs only) + ;; Macro to write a byte in \1 to main memory at \2 PUTB MACRO ; 14 cycles, 4 bytes - ;; XXX deref - move.b \1,0(a6,\2) + move.w \2,d1 + bsr deref + move.b \1,(a0) ENDM ;; Macro to read a word from main memory at register \1 ;; (unaligned). Puts the word read in \2. ;; - ;; XXX deref - ;; ;; <debrouxl> It decrements sp by 2, but stores the result at ;; sp, not at 1(sp). So you essentially get a "free" shift ;; left by 8 bits. Much faster than lsl.w / rol.w #8, at ;; least. -FETCHW MACRO - move.b 1(a6,\1.w),-(sp); 18/4 +FETCHW MACRO ; ?/16 + move.w \1,d1 ; 4/2 + bsr deref ; ?/4 + move.b (a0),-(sp) ; 18/4 move.w (sp)+,\2 ; 8/2 - move.b 0(a6,\1.w),\2 ; 14/4 + move.b (a0),\2 ; 14/4 ENDM ;; Macro to write a word in \1 to main memory at \2 (regs only) -PUTW MACRO ; 14 cycles, 4 bytes - ;; XXX ALIGNMENT - move.b \1,0(a6,\2) +PUTW MACRO ; + move.w \2,d1 + bsr deref + move.w \1,d0 + move.b d0,(a0)+ + LOHI d0 + move.b d0,(a0) ENDM ;; Push the word in \1 (register) using stack register a4. @@ -2088,6 +2094,8 @@ emu_op_e1: emu_op_e2: ;; EX (SP),HL ;; Exchange + + START emu_op_e3: START |