diff --git a/core/banks.asm b/core/banks.asm
index 9e7bcd5..f7c58cd 100644
--- a/core/banks.asm
+++ b/core/banks.asm
@@ -20,20 +20,20 @@ EXTERN init_battery
 
 SECTION .text
 
-; * Inicia ponteiros dos bancos
-; *******************************
+; * Initialize banks pointers
+; *****************************
 GLOBAL init_banks
 init_banks:
         push edi
 
-        ; Limpa a NEAR [RAM]
+        ; Clear RAM
         xor eax, eax
         mov BYTE [battery], al
         mov ecx, (40*1024)/4
-        mov edi, RAM ; mov edi, offset RAM
+        mov edi, RAM
         rep stosd
 
-        ; Inicia ponteiros dos bancos e registradores de paginação
+        ; Initialize banks pointers and page registers
         mov BYTE [RAMSelect], al
         mov eax, DWORD [ROM]
         mov DWORD [pBank0], eax
@@ -49,11 +49,11 @@ init_banks:
         pop edi
         ret
 
-; * Ler a memória
-; *****************
+; * Read memory
+; ***************
 GLOBAL read_mem
 read_mem:
-        ; Qual banco vai ler?
+        ; Which bank?
         cmp esi, 00400h
         jb RM0
         cmp esi, 04000h
@@ -63,12 +63,12 @@ read_mem:
         cmp esi, 0C000h
         jb RM3
 
-        ; Ler a NEAR [RAM] ou registradores de paginação
+        ; Read RAM or page register
         and esi, 0DFFFh
-        add esi, RAM - 0C000h ; add esi, offset RAM - 0C000h
+        add esi, RAM - 0C000h
         ret
 
-        ; Seleciona o banco para leitura
+        ; Select the right bank
 RM0:    add esi, DWORD [ROM]
         ret
 RM1:    add esi, DWORD [pBank0]
@@ -78,26 +78,26 @@ RM2:    add esi, DWORD [pBank1]
 RM3:    add esi, DWORD [pBank2]
         ret
 
-; * Escreve na memória
-; **********************
+; * Write memory
+; ****************
 GLOBAL write_mem
 write_mem:
-        ; Qual banco vai escrever?
+        ; Which bank?
         cmp esi, 08000h
         jb WM7
         cmp esi, 0C000h
         jb WM8
 
-        ; Escrever nos registradores de paginação?
+        ; Write in page registers?
         cmp esi, 0FFFCh
         jae WM1
 
-        ; Escreve na NEAR [RAM]
+        ; Write in RAM
 WM0:    and esi, 0DFFFh
-        add esi, RAM - 0C000h ; add esi, offset RAM - 0C000h
+        add esi, RAM - 0C000h
         ret
 
-        ; NEAR [RAM] Select
+        ; Select
 WM1:    cmp esi, 0FFFCh
         jne WM4
         mov BYTE [RAMSelect], al
@@ -107,7 +107,7 @@ WM1:    cmp esi, 0FFFCh
         mov DWORD [pBank2], ebx
         jmp WM0
 
-        ; Inicia bateria
+        ; Initialize battery
 WM11:   cmp BYTE [battery], 0
         jne WM2
         push eax
@@ -115,7 +115,7 @@ WM11:   cmp BYTE [battery], 0
         pop eax
         mov BYTE [battery], 1
 
-        ; Seleciona o banco da bateria
+        ; Select battery bank
 WM2:    test al, 4
         jnz WM3
         mov DWORD [pBank2], RAM_EX - 08000h
@@ -123,7 +123,7 @@ WM2:    test al, 4
 WM3:    mov DWORD [pBank2], RAM_EX - 04000h
         jmp WM0
 
-        ; Seleciona a página para o banco do DWORD [ROM]
+        ; Select ROM page
 WM4:    mov ebx, eax
         mov ah, 0
         div BYTE [ROM_size]
@@ -131,14 +131,14 @@ WM4:    mov ebx, eax
         shl eax, 14
         add eax, DWORD [ROM]
 
-        ; Banco 0
+        ; Bank 0
         cmp esi, 0FFFDh
         jne WM5
         mov DWORD [pBank0], eax
         mov eax, ebx
         jmp WM0
 
-        ; Banco 1
+        ; Bank 1
 WM5:    cmp esi, 0FFFEh
         jne WM6
         sub eax, 04000h
@@ -146,7 +146,7 @@ WM5:    cmp esi, 0FFFEh
         mov eax, ebx
         jmp WM0
 
-        ; Banco 2
+        ; Bank 2
 WM6:    sub eax, 08000h
         mov DWORD [pBank2ROM], eax
         test BYTE [RAMSelect], 8
@@ -155,7 +155,7 @@ WM6:    sub eax, 08000h
 WM66:   mov eax, ebx
         jmp WM0
 
-        ; Escreve no banco selecionado
+        ; Write in selected bank
 WM7:    mov esi, garbage
         ret
 WM8:    test BYTE [RAMSelect], 8
diff --git a/core/cpu.asm b/core/cpu.asm
index 74ba0bc..b9c614b 100644
--- a/core/cpu.asm
+++ b/core/cpu.asm
@@ -25,8 +25,8 @@ EXTERN ?OpCodeErr3@@YAXHHHH@Z
 
 SECTION .text
 
-; * Reseta a CPU
-; ****************
+; * Reset CPU
+; *************
 GLOBAL reset_CPU
 reset_CPU:
         xor eax, eax
@@ -46,8 +46,8 @@ reset_CPU:
 
         ret
 
-; * Processa uma linha
-; **********************
+; * Executes one line
+; *********************
 GLOBAL TraceLine
 TraceLine:
         inc BYTE [rR]
@@ -60,32 +60,32 @@ TLF:    cmp BYTE [TClock], 228
         jb TraceLine
         ret
 
-; * Executa interrupção BYTE [NMI] (Botão pause)
-; *****************************************
+; * NMI Interruption (pause button)
+; ***********************************
 GLOBAL int_NMI
 int_NMI:
         pusha
 
-        ; Guarda máscara de interrupção
+        ; Save interruption mask
         mov BYTE [NMI], 1
         mov al, BYTE [IFF1]
         mov BYTE [IFF2], al
         mov BYTE [IFF1], 0
 
-        ; Verifica o estado da CPU
+        ; Checks CPU state
         test BYTE [Halt], 1
         jz NMI0
         mov BYTE [Halt], 0
         inc DWORD [rPCx]
 
-        ; Empilha PC
+        ; push PC
 NMI0:   sub DWORD [rSPx], 2
         mov esi, DWORD [rSPx]
         call read_mem
         mov eax, DWORD [rPCx]
         mov [esi], ax
 
-        ; Endereço da interrupção
+        ; Jump to interruption address
         inc BYTE [rR]
         mov DWORD [rPCx], 66h
         add BYTE [TClock], 11
@@ -93,39 +93,39 @@ NMI0:   sub DWORD [rSPx], 2
         popa
         ret
 
-; * Executa interrupção
-; ***********************
+; * Z80 Interruption
+; ********************
 GLOBAL int_Z80
 int_Z80:
-        ; Verifica se a interrupção está abilitada
+        ; Checks if the interruption is enabled
         cmp BYTE [IFF1], 0
         je IZ80
 
-        ; Reseta máscaras de interrupção
+        ; Reset interruption mask
         mov BYTE [IFF1], 0
         mov BYTE [IFF2], 0
 
-        ; Verifica o estado da CPU
+        ; Checks CPU state
         test BYTE [Halt], 1
         jz Z80
         mov BYTE [Halt], 0
         inc DWORD [rPCx]
 
-        ; Empilha PC
+        ; push PC
 Z80:    sub DWORD [rSPx], 2
         mov esi, DWORD [rSPx]
         call read_mem
         mov eax, DWORD [rPCx]
         mov [esi], ax
 
-        ; Endereço da interrupção
+        ; Jump to interruption address
         inc BYTE [rR]
         mov DWORD [rPCx], 38h
         add BYTE [TClock], 13
 IZ80:   ret
 
-; * Opcode não implementado
-; ***************************
+; * Opcode not implemented (one byte)
+; *************************************
 GLOBAL _NIMP1
 _NIMP1:
         ;pusha
@@ -136,8 +136,8 @@ _NIMP1:
         ;popa
         jmp TLF
 
-; * Opcode não implementado
-; ***************************
+; * Opcode not implemented (two bytes)
+; **************************************
 GLOBAL _NIMP2
 _NIMP2:
         ;pusha
@@ -150,8 +150,8 @@ _NIMP2:
         ;popa
         jmp TLF
 
-; * Opcode não implementado
-; ***************************
+; * Opcode not implemented (three bytes)
+; ****************************************
 GLOBAL _NIMP3
 _NIMP3:
         ;pusha
@@ -166,7 +166,7 @@ _NIMP3:
         ;popa
         jmp TLF
 
-; * Opcode não Listado
+; * Opcode not listed
 ; **********************
 GLOBAL _NOLIST
 _NOLIST:
@@ -200,7 +200,7 @@ _NOLIST:
         jmp TLF
 %ENDMACRO
 
-; * Increment register %1
+; * Increment register r
 ; ************************
 %MACRO __INCr 2
         and BYTE [Flag], 1
@@ -240,7 +240,7 @@ _NOLIST:
         jmp TLF
 %ENDMACRO
 
-; * Decrement register pair %1
+; * Decrement register pair ss
 ; ******************************
 %MACRO __DECss 1
         dec WORD %1
@@ -282,7 +282,7 @@ _NOLIST:
         __LDrr %1, [esi], 7
 %ENDMACRO
 
-; * Load location (HL) with register %1
+; * Load location (HL) with register r
 ; **************************************
 %MACRO __LD_HL_r 1
         mov al, %1
@@ -310,7 +310,7 @@ _NOLIST:
         jmp TLF
 %ENDMACRO
 
-; * Add operand %1 to accumulator with carry
+; * Add operand s to accumulator with carry
 ; *******************************************
 %MACRO __ADCAs 2
         mov bl, BYTE [Flag]
@@ -328,7 +328,7 @@ _NOLIST:
         jmp TLF
 %ENDMACRO
 
-; * Subtract operand %1 from accumulator
+; * Subtract operand s from accumulator
 ; ***************************************
 %MACRO __SUBs 2
         mov BYTE [Flag], 2
@@ -344,7 +344,7 @@ _NOLIST:
         jmp TLF
 %ENDMACRO
 
-; * Subtract operand %1 from accumulator with carry
+; * Subtract operand s from accumulator with carry
 ; **************************************************
 %MACRO __SBCAs 2
         mov bl, BYTE [Flag]
@@ -362,7 +362,7 @@ _NOLIST:
         jmp TLF
 %ENDMACRO
 
-; * Logical AND of operand %1 to accumulator
+; * Logical AND of operand s to accumulator
 ; *******************************************
 %MACRO __ANDs 2
         mov BYTE [Flag], 10h
@@ -376,7 +376,7 @@ _NOLIST:
         jmp TLF
 %ENDMACRO
 
-; * Exclusive OR operand r and accumulator
+; * Exclusive OR operand s and accumulator
 ; ******************************************
 %MACRO __XORs 2
         mov al, %1
@@ -389,7 +389,7 @@ _NOLIST:
         jmp TLF
 %ENDMACRO
 
-; * Logical OR of operand %1 and accumulator
+; * Logical OR of operand s and accumulator
 ; *******************************************
 %MACRO __ORs 2
         mov al, %1
@@ -402,7 +402,7 @@ _NOLIST:
         jmp TLF
 %ENDMACRO
 
-; * Compare operand %1 with accumulator
+; * Compare operand s with accumulator
 ; **************************************
 %MACRO __CPs 2
         mov BYTE [Flag], 2
@@ -444,7 +444,7 @@ _NOLIST:
         jmp TLF
 %ENDMACRO
 
-; * Jump relative to PC+e if condition %1 is true
+; * Jump relative to PC+e if condition cc is true
 ; *************************************************
 %MACRO __JRccn 2
         test BYTE [Flag], %2
@@ -458,7 +458,7 @@ _NOLIST:
         jmp TLF
 %ENDMACRO
 
-; * Call subroutine at location nn if condition CC is true
+; * Call subroutine at location nn if condition cc is true
 ; **********************************************************
 %MACRO __CALLccnn 2
         test BYTE [Flag], %2
@@ -478,7 +478,7 @@ _NOLIST:
         jmp TLF
 %ENDMACRO
 
-; * Return from subroutine if condition %1 is true
+; * Return from subroutine if condition cc is true
 ; **************************************************
 %MACRO __RETcc 2
         test BYTE [Flag], %2
@@ -577,7 +577,7 @@ _INCDE: __INCss WORD [rE]
 _INCHL: __INCss WORD [rL]
 _INCSP: __INCss DWORD [rSPx]
 
-; * INC %1 - (04,0C,14,1C,24,2C,34,3C) - 4/11 Clk - Increment operand %1
+; * INC r - (04,0C,14,1C,24,2C,34,3C) - 4/11 Clk - Increment operand r
 ; **********************************************************************
 GLOBAL _INCB, _INCC, _INCD, _INCE, _INCH, _INCL, _INC_HL, _INCA
 _INCB:  __INCr BYTE [rB], 4
@@ -606,7 +606,7 @@ INCHL:  and ah, 11010000b
         jmp TLF
 _INCA:  __INCr BYTE [rAcc], 4
 
-; * DEC s - (05,0D,15,1D,25,2D,35,3D) - 4/11 Clk - Decrement operand s
+; * DEC r - (05,0D,15,1D,25,2D,35,3D) - 4/11 Clk - Decrement operand r
 ; **********************************************************************
 GLOBAL _DECB, _DECC, _DECD, _DECE, _DECH, _DECL, _DEC_HL, _DECA
 _DECB:  __DECr BYTE [rB], 4
@@ -636,8 +636,8 @@ DECHL:  and ah, 11010000b
         jmp TLF
 _DECA:  __DECr BYTE [rAcc], 4
 
-; * LD %1, n - (06,0E,16,1E,26,2E,3E) n - 7 Clk - Load register %1 with value n
-; *********************************************************
+; * LD r, n - (06,0E,16,1E,26,2E,3E) n - 7 Clk - Load register r with value n
+; *****************************************************************************
 GLOBAL _LDBN, _LDCN, _LDDN, _LDEN, _LDHN, _LDLN, _LDAN
 _LDBN:  __LDrn BYTE [rB]
 _LDCN:  __LDrn BYTE [rC]
@@ -920,7 +920,7 @@ _CCF:
         add BYTE [TClock], 4
         jmp TLF
 
-; * LD B, %1 - (40,41,42,43,44,45,46,47) - 4/7 Clk - Load register B with operand %1
+; * LD B, r - (40,41,42,43,44,45,46,47) - 4/7 Clk - Load register B with operand r
 ; **********************************************************************************
 GLOBAL _LDBB, _LDBC, _LDBD, _LDBE, _LDBH, _LDBL, _LDB_HL, _LDBA
 _LDBB:  __LDrr BYTE [rB], BYTE [rB], 4
@@ -932,7 +932,7 @@ _LDBL:  __LDrr BYTE [rB], BYTE [rL], 4
 _LDB_HL:__LDr_HL BYTE [rB]
 _LDBA:  __LDrr BYTE [rB], BYTE [rAcc], 4
 
-; * LD C, %1 - (48,49,4A,4B,4C,4D,4E,4F) - 4/7 Clk - Load register C with operand %1
+; * LD C, r - (48,49,4A,4B,4C,4D,4E,4F) - 4/7 Clk - Load register C with operand r
 ; **********************************************************************************
 GLOBAL _LDCB, _LDCC, _LDCD, _LDCE, _LDCH, _LDCL, _LDC_HL, _LDCA
 _LDCB:  __LDrr BYTE [rC], BYTE [rB], 4
@@ -944,7 +944,7 @@ _LDCL:  __LDrr BYTE [rC], BYTE [rL], 4
 _LDC_HL:__LDr_HL BYTE [rC]
 _LDCA:  __LDrr BYTE [rC], BYTE [rAcc], 4
 
-; * LD D, %1 - (50,51,52,53,54,55,56,57) - 4/7 Clk - Load register D with operand %1
+; * LD D, r - (50,51,52,53,54,55,56,57) - 4/7 Clk - Load register D with operand r
 ; **********************************************************************************
 GLOBAL _LDDB, _LDDC, _LDDD, _LDDE, _LDDH, _LDDL, _LDD_HL, _LDDA
 _LDDB:  __LDrr BYTE [rD], BYTE [rB], 4
@@ -956,7 +956,7 @@ _LDDL:  __LDrr BYTE [rD], BYTE [rL], 4
 _LDD_HL:__LDr_HL BYTE [rD]
 _LDDA:  __LDrr BYTE [rD], BYTE [rAcc], 4
 
-; * LD E, %1 - (58,59,5A,5B,5C,5D,5E,5F) - 4/7 Clk - Load register E with operand %1
+; * LD E, r - (58,59,5A,5B,5C,5D,5E,5F) - 4/7 Clk - Load register E with operand r
 ; **********************************************************************************
 GLOBAL _LDEB, _LDEC, _LDED, _LDEE, _LDEH, _LDEL, _LDE_HL, _LDEA
 _LDEB:  __LDrr BYTE [rE], BYTE [rB], 4
@@ -968,7 +968,7 @@ _LDEL:  __LDrr BYTE [rE], BYTE [rL], 4
 _LDE_HL:__LDr_HL BYTE [rE]
 _LDEA:  __LDrr BYTE [rE], BYTE [rAcc], 4
 
-; * LD H, %1 - (60,62,63,64,65,66,67) - 4/7 Clk - Load register H with operand %1
+; * LD H, r - (60,62,63,64,65,66,67) - 4/7 Clk - Load register H with operand r
 ; *******************************************************************************
 GLOBAL _LDHB, _LDHC, _LDHD, _LDHE, _LDHH, _LDHL, _LDH_HL, _LDHA
 _LDHB:  __LDrr BYTE [rH], BYTE [rB], 4
@@ -980,7 +980,7 @@ _LDHL:  __LDrr BYTE [rH], BYTE [rL], 4
 _LDH_HL:__LDr_HL BYTE [rH]
 _LDHA:  __LDrr BYTE [rH], BYTE [rAcc], 4
 
-; * LD L, %1 - (68,69,6A,6B,6C,6D,6E,6F) - 4/7 Clk - Load register L with operand %1
+; * LD L, r - (68,69,6A,6B,6C,6D,6E,6F) - 4/7 Clk - Load register L with operand r
 ; **********************************************************************************
 GLOBAL _LDLB, _LDLC, _LDLD, _LDLE, _LDLH, _LDLL, _LDL_HL, _LDLA
 _LDLB:  __LDrr BYTE [rL], BYTE [rB], 4
@@ -992,7 +992,7 @@ _LDLL:  __LDrr BYTE [rL], BYTE [rL], 4
 _LDL_HL:__LDr_HL BYTE [rL]
 _LDLA:  __LDrr BYTE [rL], BYTE [rAcc], 4
 
-; * LD (HL), %1 - (70,71,72,73,74,75,77) - 7 Clk - Load location (HL) with register %1
+; * LD (HL), r - (70,71,72,73,74,75,77) - 7 Clk - Load location (HL) with register r
 ; ************************************************************************************
 GLOBAL _LD_HL_B, _LD_HL_C, _LD_HL_D, _LD_HL_E, _LD_HL_H, _LD_HL_L, _LD_HL_A
 _LD_HL_B:__LD_HL_r BYTE [rB]
@@ -1011,7 +1011,7 @@ _HALT:
         add BYTE [TClock], 4
         jmp TLF
 
-; * LD A, %1 - (78,79,7A,7B,7C,7D,7E,7F) - 4/7 Clk - Load register A with operand %1
+; * LD A, r - (78,79,7A,7B,7C,7D,7E,7F) - 4/7 Clk - Load register A with operand r
 ; **********************************************************************************
 GLOBAL _LDAB, _LDAC, _LDAD, _LDAE, _LDAH, _LDAL, _LDA_HL, _LDAA
 _LDAB:  __LDrr BYTE [rAcc], BYTE [rB], 4
@@ -1377,7 +1377,7 @@ _FD:
 ; * Macros
 ; ***************************************************************************************
 
-; * Rotate operand %1 left circular
+; * Rotate operand m left circular
 ; **********************************
 %MACRO __RLCr 3
         rol %1, 1
@@ -1392,7 +1392,7 @@ _FD:
         jmp TLF
 %ENDMACRO
 
-; * Rotate operand %1 right circular
+; * Rotate operand m right circular
 ; ***********************************
 %MACRO __RRCr 3
         ror %1, 1
@@ -1439,7 +1439,7 @@ _FD:
         jmp TLF
 %ENDMACRO
 
-; * Load output port (C) with register %1
+; * Load output port (C) with register r
 ; ****************************************
 %MACRO __OUT_C_r 1
         mov al, %1
@@ -1464,7 +1464,7 @@ _FD:
         jmp TLF
 %ENDMACRO
 
-; * Load location (I$+d) with register %1
+; * Load location (I$+d) with register r
 ; ****************************************
 %MACRO __LDIdr 3
         mov al, %2
@@ -1487,7 +1487,7 @@ _FD:
         jmp TLF
 %ENDMACRO
 
-; * Set bit %1 of location (HL)
+; * Set bit b of location (HL)
 ; ******************************
 %MACRO __SETb_HL 1
         movzx esi, WORD [rL]
@@ -1503,7 +1503,7 @@ _FD:
         jmp TLF
 %ENDMACRO
 
-; * Set bit %1 of location (I$+d)
+; * Set bit b of location (I$+d)
 ; ********************************
 %MACRO __SETb_Id 2
         movsx esi, BYTE [esi+2]
@@ -1513,7 +1513,7 @@ _FD:
         __SETbr %1, BYTE [esi], 23, 4
 %ENDMACRO
 
-; * Reset bit %1 of register r
+; * Reset bit b of register r
 ; *****************************
 %MACRO __RESbr 4
         and %2, ~%1
@@ -1522,7 +1522,7 @@ _FD:
         jmp TLF
 %ENDMACRO
 
-; * Reset bit %1 of location (HL)
+; * Reset bit b of location (HL)
 ; ********************************
 %MACRO __RESb_HL 1
         movzx esi, WORD [rL]
@@ -1538,7 +1538,7 @@ _FD:
         jmp TLF
 %ENDMACRO
 
-; * Reset bit %1 of location (I$+d)
+; * Reset bit b of location (I$+d)
 ; **********************************
 %MACRO __RESb_Id 2
         movsx esi, BYTE [esi+2]
@@ -1548,7 +1548,7 @@ _FD:
         __RESbr %1, BYTE [esi], 23, 4
 %ENDMACRO
 
-; * Test bit %1 of register r
+; * Test bit b of register r
 ; ****************************
 %MACRO __BITbr 4
         and BYTE [Flag], 1
@@ -1562,7 +1562,7 @@ _FD:
         jmp TLF
 %ENDMACRO
 
-; * Test bit %1 of location (HL)
+; * Test bit b of location (HL)
 ; *******************************
 %MACRO __BITb_HL 1
         movzx esi, WORD [rL]
@@ -1570,7 +1570,7 @@ _FD:
         __BITbr %1, BYTE [esi], 12, 2
 %ENDMACRO
 
-; * Test bit %1 of location (I$+d)
+; * Test bit b of location (I$+d)
 ; *******************************
 %MACRO __BITb_Id 2
         movsx esi, BYTE [esi+2]
@@ -2421,22 +2421,22 @@ _ADCA_IXd:
         call read_mem
         __ADCAs [esi], 19
 
-; SUB IXH - DD 94 - 8 Clk - Subtract IXH from accumulator
-; *********************************************************
+; * SUB IXH - DD 94 - 8 Clk - Subtract IXH from accumulator
+; ***********************************************************
 GLOBAL _SUBIXH
 _SUBIXH:
         inc DWORD [rPCx]
         __SUBs BYTE [rIX+1], 8
 
-; SUB IXL - DD 95 - 8 Clk - Subtract IXL from accumulator
-; *********************************************************
+; * SUB IXL - DD 95 - 8 Clk - Subtract IXL from accumulator
+; ***********************************************************
 GLOBAL _SUBIXL
 _SUBIXL:
         inc DWORD [rPCx]
         __SUBs BYTE [rIX], 8
 
-; SUB (IX+d) - DD 96 d - 19 Clk - Subtract location (IX+d) from accumulator
-; ***************************************************************************
+; * SUB (IX+d) - DD 96 d - 19 Clk - Subtract location (IX+d) from accumulator
+; *****************************************************************************
 GLOBAL _SUB_IXd
 _SUB_IXd:
         add DWORD [rPCx], 2
@@ -2446,8 +2446,8 @@ _SUB_IXd:
         call read_mem
         __SUBs [esi], 19
 
-; SBC A, (IX+d) - DD 9E d - 19 Clk - Subtract location (IX+d) from accumulator with carry
-; *****************************************************************************************
+; * SBC A, (IX+d) - DD 9E d - 19 Clk - Subtract location (IX+d) from accumulator with carry
+; *******************************************************************************************
 GLOBAL _SBCA_IXd
 _SBCA_IXd:
         add DWORD [rPCx], 2
@@ -2594,7 +2594,7 @@ _JP_IX:
         jmp TLF
 
 ; * LD SP, IX - DD F9 - 10 Clk - Load SP with IX
-; *********************************************
+; ************************************************
 GLOBAL _LDSPIX
 _LDSPIX:
         mov eax, DWORD [rIX]
@@ -2786,7 +2786,7 @@ _RETN:
         add BYTE [TClock], 14
         jmp TLF
 
-; * BYTE [IM] 0 - ED (46,56,5E) - 8 Clk - Set interrupt mode m
+; * IM 0 - ED (46,56,5E) - 8 Clk - Set interrupt mode m
 ; *******************************************************
 GLOBAL _IM0, _IM1, _IM2
 _IM0:   __IM 0
@@ -3436,22 +3436,22 @@ _ADCA_IYd:
         call read_mem
         __ADCAs [esi], 19
 
-; SUB IYH - FD 94 - 8 Clk - Subtract IYH from accumulator
-; *********************************************************
+; * SUB IYH - FD 94 - 8 Clk - Subtract IYH from accumulator
+; ***********************************************************
 GLOBAL _SUBIYH
 _SUBIYH:
         inc DWORD [rPCx]
         __SUBs BYTE [rIY+1], 8
 
-; SUB IYL - FD 95 - 8 Clk - Subtract IYL from accumulator
-; *********************************************************
+; * SUB IYL - FD 95 - 8 Clk - Subtract IYL from accumulator
+; ***********************************************************
 GLOBAL _SUBIYL
 _SUBIYL:
         inc DWORD [rPCx]
         __SUBs BYTE [rIY], 8
 
-; SUB (IY+d) - FD 96 d - 19 Clk - Subtract location (IY+d) from accumulator
-; ***************************************************************************
+; * SUB (IY+d) - FD 96 d - 19 Clk - Subtract location (IY+d) from accumulator
+; *****************************************************************************
 GLOBAL _SUB_IYd
 _SUB_IYd:
         add DWORD [rPCx], 2
@@ -3461,8 +3461,8 @@ _SUB_IYd:
         call read_mem
         __SUBs [esi], 19
 
-; SBC A, (IY+d) - FD 9E d - 19 Clk - Subtract location (IY+d) from accumulator with carry
-; *****************************************************************************************
+; * SBC A, (IY+d) - FD 9E d - 19 Clk - Subtract location (IY+d) from accumulator with carry
+; *******************************************************************************************
 GLOBAL _SBCA_IYd
 _SBCA_IYd:
         add DWORD [rPCx], 2
@@ -3732,7 +3732,7 @@ _SET7_IYd:__SETb_Id 80h, DWORD [rIY]
 
 SECTION .data
 
-; Tabela de opcodes
+; Opcode table
 GLOBAL Opcode
 Opcode:
     ;   0/8       1/9       2/A       3/B       4/C       5/D       6/E       7/F
@@ -3769,7 +3769,7 @@ Opcode:
     DD _RETP,    _POPAF,   _JPPN,    _DI,      _CALLPN,  _PUSHAF,  _ORN,     _RST30
     DD _RETM,    _LDSPHL,  _JPMN,    _EI,      _CALLMN,  _FD,      _CPN,     _RST38     ; F
 
-; Tabela de opcodes (CB)
+; Opcode table  (CB)
 GLOBAL OpcodeCB
 OpcodeCB:
     ;   0/8       1/9       2/A       3/B       4/C       5/D       6/E       7/F
@@ -3806,7 +3806,7 @@ OpcodeCB:
     DD _SET6B,   _SET6C,   _SET6D,   _SET6E,   _SET6H,   _SET6L,   _SET6_HL, _SET6A
     DD _SET7B,   _SET7C,   _SET7D,   _SET7E,   _SET7H,   _SET7L,   _SET7_HL, _SET7A     ; F
 
-; Tabela de opcodes (DD)
+; Opcode table (DD)
 GLOBAL OpcodeDD
 OpcodeDD:
     ;   0/8       1/9       2/A       3/B       4/C       5/D       6/E       7/F
@@ -3843,7 +3843,7 @@ OpcodeDD:
     DD _NOP,     _NOP,     _NOP,     _NOP,     _NOP,     _NOP,     _NOP,     _NOP
     DD _NOP,     _LDSPIX,  _NOP,     _NOP,     _NOP,     _NOP,     _NOP,     _NOP       ; F
 
-; Tabela de opcodes (DD CB)
+; Opcode table (DD CB)
 GLOBAL OpcodeDDCB
 OpcodeDDCB:
     ;   0/8       1/9       2/A       3/B       4/C       5/D       6/E       7/F
@@ -3880,7 +3880,7 @@ OpcodeDDCB:
     DD _NIMP3,   _NIMP3,   _NIMP3,   _NIMP3,   _NIMP3,   _NIMP3,   _SET6_IXd,_NIMP3
     DD _NIMP3,   _NIMP3,   _NIMP3,   _NIMP3,   _NIMP3,   _NIMP3,   _SET7_IXd,_NIMP3     ; F
 
-; Tabela de opcodes (ED)
+; Opcode table (ED)
 GLOBAL OpcodeED
 OpcodeED:
     ;   0/8       1/9       2/A       3/B       4/C       5/D       6/E       7/F
@@ -3917,7 +3917,7 @@ OpcodeED:
     DD _NOLIST,  _NOLIST,  _NOLIST,  _NOLIST,  _NOLIST,  _NOLIST,  _NOLIST,  _NOLIST
     DD _NOLIST,  _NOLIST,  _NOLIST,  _NOLIST,  _NOLIST,  _NOLIST,  _NOLIST,  _NOLIST    ; F
 
-; Tabela de opcodes (FD)
+; Opcode table (FD)
 GLOBAL OpcodeFD
 OpcodeFD:
     ;   0/8       1/9       2/A       3/B       4/C       5/D       6/E       7/F
@@ -3954,7 +3954,7 @@ OpcodeFD:
     DD _NOP,     _NOP,     _NOP,     _NOP,     _NOP,     _NOP,     _NOP,     _NOP
     DD _NOP,     _LDSPIY,  _NOP,     _NOP,     _NOP,     _NOP,     _NOP,     _NOP       ; F
 
-; Tabela de opcodes (FD CB)
+; Opcode table (FD CB)
 GLOBAL OpcodeFDCB
 OpcodeFDCB:
     ;   0/8       1/9       2/A       3/B       4/C       5/D       6/E       7/F
diff --git a/core/data.asm b/core/data.asm
index a5a03aa..a3b045e 100644
--- a/core/data.asm
+++ b/core/data.asm
@@ -96,9 +96,9 @@ NoiseFreq2  RESB 1
 
 ; **** VDP ****
 GLOBAL VDPStatus, cVDP, VDPLow
-VDPStatus   RESB 1          ; Status do VDP
-cVDP        RESB 1          ; Primeira ou segunda escrita na porta BFh
-VDPLow      RESB 1          ; Valor auxiliar de escrita na porta BFh
+VDPStatus   RESB 1
+cVDP        RESB 1          ; First or second write in BFh port
+VDPLow      RESB 1          ; Temporary value for BFh port
 
 GLOBAL pRAM, VDPR, CRAM, VRAM
 pRAM    RESD 1              ; Pointer for palette or video memory
diff --git a/core/data.inc b/core/data.inc
index 0d581d8..a09fe9d 100644
--- a/core/data.inc
+++ b/core/data.inc
@@ -1,19 +1,3 @@
-; Alis, A SEGA Master System emulator
-; Copyright (C) 2002-2014 Cidorvan Leite
-
-; This program is free software: you can redistribute it and/or modify
-; it under the terms of the GNU General Public License as published by
-; the Free Software Foundation, either version 3 of the License, or
-; (at your option) any later version.
-
-; This program is distributed in the hope that it will be useful,
-; but WITHOUT ANY WARRANTY; without even the implied warranty of
-; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-; GNU General Public License for more details.
-
-; You should have received a copy of the GNU General Public License
-; along with this program.  If not, see [http://www.gnu.org/licenses/].
-
 ; **** BANKS ****
 EXTERN pBank0, pBank1, pBank2, pBank2ROM, battery, RAMSelect
 
diff --git a/core/io.asm b/core/io.asm
index 35d4480..118ec95 100644
--- a/core/io.asm
+++ b/core/io.asm
@@ -22,41 +22,25 @@
 
 SECTION .text
 
-; * Porta para escrita não implementada
-; ***************************************
+; * Write port not implemented
+; ******************************
 GLOBAL _NWIMP
 _NWIMP:
-        ;movzx eax, al
-        ;push eax
-        ;push edx
-        ;push DWORD [rPC]
-        ;call ?WriteIOErr@@YAXHHH@Z
-        ;add esp, 12
         ret
 
-; * Porta para leitura não implementada
-; ***************************************
+; * Read port not implemented
+; *****************************
 GLOBAL _NRIMP
 _NRIMP:
-        ;push edx
-        ;push DWORD [rPC]
-        ;call ?ReadIOErr@@YAXHH@Z
-        ;add esp, 8
         ret
 
-; * Nada (R)
-; ************
-GLOBAL NadaR
-NadaR:
+; * Nothing to read
+; *******************
+GLOBAL Empty
+Empty:
         mov al, 0FFh
         ret
 
-; * Nada (W)
-; ************
-GLOBAL NadaW
-NadaW:
-        ret
-
 ; * 3E Memory Control (W)
 ; *************************
 GLOBAL MemCtrl
@@ -113,7 +97,7 @@ WVDPD:
         cmp esi, 0
         je WVDPD1
         inc DWORD [pRAM]
-        cmp DWORD [pRAM], VRAM + 4000h ; cmp DWORD [pRAM], offset VRAM + 4000h
+        cmp DWORD [pRAM], VRAM + 4000h
         jb WVDPD0
         sub DWORD [pRAM], 4000h
 WVDPD0: mov [esi], al
@@ -134,38 +118,34 @@ _RVDPS:
 ; **********************
 GLOBAL WVDPA
 WVDPA:
-        ; Primeira ou segunda escrita?
+        ; First or second time?
         test BYTE [cVDP], 1
         jnz WVDPA0
         mov BYTE [VDPLow], al
         jmp WVDPAF
 
-        ; BYTE [VRAM] endereço
+        ; VRAM address
 WVDPA0: test al, 80h
         jnz WVDPA1
-;       mov bl, al
         and al, 3Fh
         mov ah, al
         mov al, BYTE [VDPLow]
         movzx eax, ax
-        add eax, VRAM ; add eax, offset VRAM
-;       test bl, 40h
-;       jnz WVDPA00
-;       inc eax
+        add eax, VRAM
 WVDPA00:mov DWORD [pRAM], eax
         jmp WVDPAF
 
-        ; PALRAM endereço
+        ; PAL RAM address
 WVDPA1: test al, 40h
         jz WVDPA2
         mov al, BYTE [VDPLow]
         and al, 1Fh
         movzx eax, al
-        add eax, CRAM ; add eax, offset CRAM
+        add eax, CRAM
         mov DWORD [pRAM], eax
         jmp WVDPAF
 
-        ; Registros do VDP
+        ; VDP registers
 WVDPA2: and al, 0Fh
         movzx edx, al
         mov al, BYTE [VDPLow]
@@ -232,9 +212,9 @@ SECTION .data
 GLOBAL read_io
 read_io:
 ;       0/8       1/9       2/A       3/B       4/C       5/D       6/E       7/F
-    DD NadaR,    _NRIMP,   _NRIMP,   _NRIMP,   _NRIMP,   _NRIMP,   _NRIMP,   _NRIMP
+    DD Empty,    _NRIMP,   _NRIMP,   _NRIMP,   _NRIMP,   _NRIMP,   _NRIMP,   _NRIMP
     DD _NRIMP,   _NRIMP,   _NRIMP,   _NRIMP,   _NRIMP,   _NRIMP,   _NRIMP,   _NRIMP     ; 0
-    DD NadaR,    _NRIMP,   _NRIMP,   _NRIMP,   _NRIMP,   _NRIMP,   _NRIMP,   _NRIMP
+    DD Empty,    _NRIMP,   _NRIMP,   _NRIMP,   _NRIMP,   _NRIMP,   _NRIMP,   _NRIMP
     DD _NRIMP,   _NRIMP,   _NRIMP,   _NRIMP,   _NRIMP,   _NRIMP,   _NRIMP,   _NRIMP     ; 1
     DD _NRIMP,   _NRIMP,   _NRIMP,   _NRIMP,   _NRIMP,   _NRIMP,   _NRIMP,   _NRIMP
     DD _NRIMP,   _NRIMP,   _NRIMP,   _NRIMP,   _NRIMP,   _NRIMP,   _NRIMP,   _NRIMP     ; 2
@@ -292,19 +272,19 @@ write_io:
     DD _NWIMP,   _NWIMP,   _NWIMP,   _NWIMP,   _NWIMP,   _NWIMP,   _NWIMP,   _NWIMP     ; A
     DD _NWIMP,   _NWIMP,   _NWIMP,   _NWIMP,   _NWIMP,   _NWIMP,   _NWIMP,   _NWIMP
     DD _NWIMP,   _NWIMP,   _NWIMP,   _NWIMP,   _NWIMP,   WVDPA,    WVDPD,    WVDPA      ; B
-    DD NadaW,    _NWIMP,   _NWIMP,   _NWIMP,   _NWIMP,   _NWIMP,   _NWIMP,   _NWIMP
+    DD _NWIMP,   _NWIMP,   _NWIMP,   _NWIMP,   _NWIMP,   _NWIMP,   _NWIMP,   _NWIMP
     DD _NWIMP,   _NWIMP,   _NWIMP,   _NWIMP,   _NWIMP,   _NWIMP,   _NWIMP,   _NWIMP     ; C
     DD _NWIMP,   _NWIMP,   _NWIMP,   _NWIMP,   _NWIMP,   _NWIMP,   _NWIMP,   _NWIMP
-    DD _NWIMP,   _NWIMP,   _NWIMP,   _NWIMP,   _NWIMP,   _NWIMP,   NadaW,    NadaW      ; D
+    DD _NWIMP,   _NWIMP,   _NWIMP,   _NWIMP,   _NWIMP,   _NWIMP,   _NWIMP,   _NWIMP     ; D
     DD _NWIMP,   _NWIMP,   _NWIMP,   _NWIMP,   _NWIMP,   _NWIMP,   _NWIMP,   _NWIMP
     DD _NWIMP,   _NWIMP,   _NWIMP,   _NWIMP,   _NWIMP,   _NWIMP,   _NWIMP,   _NWIMP     ; E
     DD YMAR,     YMDR,     YMCRW,    _NWIMP,   _NWIMP,   _NWIMP,   _NWIMP,   _NWIMP
-    DD _NWIMP,   _NWIMP,   _NWIMP,   _NWIMP,   _NWIMP,   _NWIMP,   NadaW,    NadaW      ; F
+    DD _NWIMP,   _NWIMP,   _NWIMP,   _NWIMP,   _NWIMP,   _NWIMP,   _NWIMP,   _NWIMP     ; F
 
 
 SECTION .bss
 
-; Portas do joystick
+; Joystick ports
 GLOBAL Joy1, Joy2
 Joy1    RESB 1
 Joy2    RESB 1
diff --git a/core/psg.asm b/core/psg.asm
index a923238..13a6f78 100644
--- a/core/psg.asm
+++ b/core/psg.asm
@@ -15,18 +15,18 @@
 ; along with this program.  If not, see [http://www.gnu.org/licenses/].
 
 
-FREQUENCE   EQU 44160
-BUFFERSIZE  EQU FREQUENCE / 60
+FREQUENCY   EQU 44160
+BUFFERSIZE  EQU FREQUENCY / 60
 
 %INCLUDE "data.inc"
 
 SECTION .text
 
-; * Reseta o som
-; ****************
+; * Reset sound system
+; **********************
 GLOBAL reset_PSG
 reset_PSG:
-        ; Limpa os registradores de som
+        ; Clear sound registers
         xor eax, eax
         mov DWORD [rVol1], eax
         mov DWORD [rFreq1], eax
@@ -35,22 +35,22 @@ reset_PSG:
         mov DWORD [rFreq4], eax
         mov DWORD [rLast], eax
 
-        ; Inicia ruído
+        ; Initialize noise
         mov DWORD [Noise], 1
         mov DWORD [FeedBack], 8000h
         mov BYTE [NoiseFreq2], al
 
-        ; Inicia Períodos
-        mov BYTE [Sinal], al
-        mov DWORD [Periodo1], FREQUENCE
-        mov DWORD [Periodo2], FREQUENCE
-        mov DWORD [Periodo3], FREQUENCE
-        mov DWORD [Periodo4], eax
+        ; Initialize periods
+        mov BYTE [Signal], al
+        mov DWORD [Period1], FREQUENCY
+        mov DWORD [Period2], FREQUENCY
+        mov DWORD [Period3], FREQUENCY
+        mov DWORD [Period4], eax
 
         ret
 
-; * Escreve dados nos registradores de som
-; ******************************************
+; * Write in sound registers
+; ****************************
 GLOBAL write_PSG
 write_PSG:
         test al, 80h
@@ -67,7 +67,7 @@ write_PSG:
         mov BYTE [rVol1+ebx], al
         ret
 
-        ; Frequência (1º escrita)
+        ; Frequency (first write)
 PSGW0:  cmp bl, 3
         je PSGW01
         and al, 0Fh
@@ -82,13 +82,13 @@ PSGW0:  cmp bl, 3
 PSGW00: mov DWORD [rLast], ebx
         ret
 
-        ; Ruído
+        ; Noise
 PSGW01: test al, 4
         jnz PSGW02
         mov DWORD [Noise], 1
-        mov DWORD [FeedBack], 08000h    ; Periodic DWORD [Noise]
+        mov DWORD [FeedBack], 08000h    ; Periodic noise
         jmp PSGW03
-PSGW02: mov DWORD [FeedBack], 0F037h    ; White DWORD [Noise]
+PSGW02: mov DWORD [FeedBack], 0F037h    ; White noise
 PSGW03: and al, 3
         cmp al, 3
         je PSGW04
@@ -103,7 +103,7 @@ PSGW04: mov BYTE [NoiseFreq2], 1
         mov DWORD [rFreq4], eax
         ret
 
-        ; Frequência (2º escrita)
+        ; Frequency (second write)
 PSGW1:  mov ebx, DWORD [rLast]
         shl eax, 4
         and eax, 3F0h
@@ -117,8 +117,8 @@ PSGW1:  mov ebx, DWORD [rLast]
         or DWORD [rFreq4], eax
 PSGW2:  ret
 
-; * Atualiza o buffer
-; *********************
+; * Updates buffer
+; ******************
 GLOBAL make_PSG
 make_PSG:
         push ebx
@@ -127,80 +127,67 @@ make_PSG:
         push ebp
         mov esi, [esp+24]   ; Second parameter (stream)
 
-        ; Limpa o Buffer
+        ; Clear buffer
         mov eax, 80808080h
         mov ecx, BUFFERSIZE / 4
         mov edi, esi
         rep stosd
 
-        ; Gera canal 1
+        ; Generates channel 1
         mov al, BYTE [rVol1]
-;       shl al, 1
         mov ah, 1
-        test BYTE [Sinal], ah
+        test BYTE [Signal], ah
         jz MPS01
         neg al
 MPS01:  mov ebx, DWORD [rFreq1]
         movzx ebx, WORD [Frequencia+ebx*2]
-        cmp ebx, FREQUENCE
+        cmp ebx, FREQUENCY
         ja MPS2
-        mov edx, DWORD [Periodo1]
+        mov edx, DWORD [Period1]
         call square_wave
-        mov DWORD [Periodo1], edx
-;       jmp MPS2
-;MPS1:  call LineWave
-;       mov DWORD [Periodo1], FREQUENCE
+        mov DWORD [Period1], edx
 
-        ; Gera canal 2
+        ; Generates channel 2
 MPS2:   mov al, BYTE [rVol2]
-;       shl al, 1
         mov ah, 2
-        test BYTE [Sinal], ah
+        test BYTE [Signal], ah
         jz MPS02
         neg al
 MPS02:  mov ebx, DWORD [rFreq2]
         movzx ebx, WORD [Frequencia+ebx*2]
-        cmp ebx, FREQUENCE
+        cmp ebx, FREQUENCY
         ja MPS4
-        mov edx, DWORD [Periodo2]
+        mov edx, DWORD [Period2]
         call square_wave
-        mov DWORD [Periodo2], edx
-;       jmp MPS4
-;MPS3:  call LineWave
-;MPS31: mov DWORD [Periodo2], FREQUENCE
+        mov DWORD [Period2], edx
 
-        ; Gera canal 3
+        ; Generates channel 3
 MPS4:   mov al, BYTE [rVol3]
-;       shl al, 1
         mov ah, 4
-        test BYTE [Sinal], ah
+        test BYTE [Signal], ah
         jz MPS04
         neg al
 MPS04:  mov ebx, DWORD [rFreq3]
         movzx ebx, WORD [Frequencia+ebx*2]
-        cmp ebx, FREQUENCE
+        cmp ebx, FREQUENCY
         ja MPS6
-        mov edx, DWORD [Periodo3]
+        mov edx, DWORD [Period3]
         call square_wave
-        mov DWORD [Periodo3], edx
-;       jmp MPS6
-;MPS5:  call LineWave
-;MPS51: mov DWORD [Periodo3], FREQUENCE
+        mov DWORD [Period3], edx
 
-        ; Gera canal 4
+        ; Generates channel 4
 MPS6:   mov ah, BYTE [rVol4]
         shl ah, 1
         mov ebx, DWORD [rFreq4]
-;       shr ebx, 1
         movzx ebx, WORD [Frequencia+ebx*2]
-        cmp ebx, FREQUENCE
+        cmp ebx, FREQUENCY
         ja MPS66
         mov ecx, BUFFERSIZE
-        mov edx, DWORD [Periodo4]
+        mov edx, DWORD [Period4]
         mov ebp, DWORD [FeedBack]
         mov edi, esi
         call WPNoise
-        mov DWORD [Periodo4], edx
+        mov DWORD [Period4], edx
 
 MPS66:  pop ebp
         pop edi
@@ -208,27 +195,8 @@ MPS66:  pop ebp
         pop ebx
         ret
 
-; * Gera uma linha na altura do volume
-; **************************************
-;GLOBAL LineWave
-;LineWave:
-;       mov ecx, BUFFERSIZE / 4
-;       mov edi, SoundBuffer ; ;        mov edi, offset SoundBuffer
-;       mov bl, al
-;       shl eax, 8
-;       mov al, bl
-;       shl eax, 8
-;       mov al, bl
-;       shl eax, 8
-;       mov al, bl
-;LW0:   add [edi], eax
-;       add edi, 4
-;       dec ecx
-;       jnz LW0
-;       ret
-
-; * Gera uma onda quadrada
-; **************************
+; * Generates a squera wave
+; ***************************
 GLOBAL square_wave
 square_wave:
         mov ecx, BUFFERSIZE
@@ -244,14 +212,14 @@ SW0:    jecxz SW1
         jg SW0
 
         neg al
-        xor BYTE [Sinal], ah
-        add edx, FREQUENCE
+        xor BYTE [Signal], ah
+        add edx, FREQUENCY
         jmp SW0
 
 SW1:    ret
 
-; * Gera ruído branco ou periódico
-; **********************************
+; * Generates a white or periodic noise
+; ***************************************
 GLOBAL WPNoise
 WPNoise:
         test DWORD [Noise], 1
@@ -262,7 +230,7 @@ WPN0:   mov al, ah
         xor DWORD [Noise], ebp
 WPN1:   shr DWORD [Noise], 1
 
-        add edx, FREQUENCE
+        add edx, FREQUENCY
 WPN2:   jecxz WPN3
         add [edi], al
         inc edi
@@ -276,7 +244,7 @@ WPN3:   ret
 
 SECTION .data
 
-; Tabela de frequências
+; Frequency table
 GLOBAL Frequencia
 Frequencia:
     DW 0FFFFh, 0FFFFh, 0FFFFh, 0FFFFh, 0F424h, 0C350h, 0A2C2h, 08B82h, 07A12h, 06C81h, 061A8h
@@ -378,9 +346,9 @@ Frequencia:
 SECTION .bss
 
 ; Channels period
-GLOBAL Sinal, Periodo1, Periodo2, Periodo3, Periodo4
-Sinal       RESB 1
-Periodo1    RESD 1
-Periodo2    RESD 1
-Periodo3    RESD 1
-Periodo4    RESD 1
+GLOBAL Signal, Period1, Period2, Period3, Period4
+Signal      RESB 1
+Period1     RESD 1
+Period2     RESD 1
+Period3     RESD 1
+Period4     RESD 1
diff --git a/core/vdp.asm b/core/vdp.asm
index 8e0a9f8..ccf9c6e 100644
--- a/core/vdp.asm
+++ b/core/vdp.asm
@@ -21,20 +21,20 @@
 
 SECTION .text
 
-; * Reseta VDP
-; **************
+; * Reset VDP
+; *************
 GLOBAL reset_VDP
 reset_VDP:
         push edi
 
-        ; Inicia VDP Control
+        ; Initialize VDP controls
         xor eax, eax
         mov BYTE [cVDP], al
         mov BYTE [VDPLow], al
         mov BYTE [VDPStatus], al
         mov BYTE [LineInt], al
 
-        ; Limpa registradores, palheta de cores e memória de vídeo
+        ; Clear registers, palette and video memory
         mov ecx, (4+16+32+4000h)/4
         mov edi, pRAM
         rep stosd
@@ -42,8 +42,8 @@ reset_VDP:
         pop edi
         ret
 
-; * Gera um frame
-; *****************
+; * Render a frame
+; ******************
 GLOBAL scan_frame
 scan_frame:
         push ebx
@@ -51,13 +51,13 @@ scan_frame:
         push edi
         push ebp
 
-        ; Limpa o frame
+        ; Clear buffer
         xor eax, eax
         mov ecx, 256 * 192
-        mov edi, [esp+20]		; Param buffer
+        mov edi, [esp+20]       ; Param buffer
         rep stosd
 
-        ; Começa um novo frame
+        ; Start a new frame
         mov DWORD [ScanLine], 0
         mov al, BYTE [VDPR+10]  ; Line Counter
         cmp al, 192
@@ -65,10 +65,10 @@ scan_frame:
         dec al
 SF00:   mov BYTE [VDPCounter], al
 
-        ; Processa cada scanline
+        ; Executes each scanline
 SF0:    call TraceLine
 
-        ; Renderiza este scanline
+        ; Renders last scanline
         cmp DWORD [ScanLine], 192
         jae SF1
         test BYTE [VDPR+1], 40h
@@ -79,42 +79,41 @@ SF0:    call TraceLine
         je SF1
         call render_background_layer2
 
-        ; Linhas 0-192
+        ; Lines 0-192
 SF1:    cmp DWORD [ScanLine], 192
         ja SF5
 
-        ; Seta bit 7 do VDP Status se a linha for igual a 192
+        ; Frame Interrupt on line 192
         jne SF2
         or BYTE [VDPStatus], 80h    ; Frame Interrupt pendente
 
-        ; Checa Line Interrupt
+        ; Checks Line Interrupt
 SF2:    cmp BYTE [VDPCounter], 0
         jne SF3
-        mov al, BYTE [VDPR+10]  ; Line Counter
+        mov al, BYTE [VDPR+10]      ; Line Counter
         mov BYTE [VDPCounter], al
-        mov BYTE [LineInt], 1       ; Line Interrupt pendente
+        mov BYTE [LineInt], 1       ; Line Interrupt pending
         jmp SF4
 
-        ; Decrementa o contador do Line Interrupt
 SF3:    dec BYTE [VDPCounter]
 
-        ; Se a interrupção está pendente e abilitada, gere-a
+        ; Trigger Line Interruption
         cmp BYTE [LineInt], 0
         je SF6
-SF4:    test BYTE [VDPR+0], 10h ; Line Interrupt
+SF4:    test BYTE [VDPR+0], 10h     ; Line Interrupt
         jz SF6
         call int_Z80
         jmp SF6
 
-        ; Linhas 193-261
-SF5:    mov al, BYTE [VDPR+10]  ; Line Counter
+        ; Lines 193-261
+SF5:    mov al, BYTE [VDPR+10]      ; Line Counter
         mov BYTE [VDPCounter], al
 
         cmp DWORD [ScanLine], 224
         jae SF6
         test BYTE [VDPStatus], 80h  ; Frame Interrupt pendente
         jz SF6
-        test BYTE [VDPR+1], 20h ; Frame Interrupt
+        test BYTE [VDPR+1], 20h     ; Frame Interrupt
         jz SF6
         call int_Z80
 
@@ -129,23 +128,11 @@ SF6:    sub BYTE [TClock], 228
         pop ebx
         ret
 
-; * Renderiza uma linha
-; ***********************
+; * Render one line
+; *******************
 render_background_layer:
         mov BYTE [RenderBL2], 0
 
-;       mov eax, DWORD [ScanLine]
-;       shr eax, 3
-;       shl eax, 6
-;       mov esi, VRAM
-;       add esi, eax
-;       movzx eax, BYTE [VDPR+2]
-;       shl eax, 10
-;       and eax, 3800h
-;       add eax, 48
-;       add esi, eax
-;       mov scrolly, esi
-
         movzx eax, BYTE [VDPR+9]
         add eax, DWORD [ScanLine]
         cmp eax, 224
@@ -163,12 +150,12 @@ RL000:  shr eax, 3
 
         mov eax, DWORD [ScanLine]
         shl eax, 10
-        mov edi, [esp+24]			; Param buffer (after one call instruction)
+        mov edi, [esp+24]           ; Param buffer (after one call instruction)
         add edi, eax
 
         mov DWORD [scrollx], 0
 
-        ; Ocuta as duas primeiras linhas
+        ; Hide first two lines
         test BYTE [VDPR+0], 40h
         jz RL00
         cmp DWORD [ScanLine], 16
@@ -184,22 +171,15 @@ RL01:   movzx ebx, BYTE [VDPR+9]
         shl ebx, 2
 
         mov ch, 32
-RL0:;   cmp ch, 8
-;       jne RL_0
-;       mov esi, scrolly
 RL_0:   movzx edx, WORD [esi]
         add esi, 2
 
-        ; Usar palheta do sprite?
+        ; Sprite palette?
         mov DWORD [pal], edx
         and DWORD [pal], 0800h
         shr DWORD [pal], 7
-;       mov DWORD [pal], 0                      *
-;       test byte ptr [esi-1], 8h       * 
-;       jz RL_00                        * Obsoleto
-;       mov DWORD [pal], 16                     *
 
-RL_00:  test BYTE [esi-1], 10h  ; Tile na frente do sprite (renderiza depois)
+RL_00:  test BYTE [esi-1], 10h      ; Tile in front layer (renders after)
         jz RL11
         mov BYTE [RenderBL2], 1
         mov eax, DWORD [pal]
@@ -233,19 +213,19 @@ RL_00:  test BYTE [esi-1], 10h  ; Tile na frente do sprite (renderiza depois)
         and edx, 3FFh
         mov DWORD [scrollx], edx
         dec ch
-        jnz RL0
+        jnz RL_0
         ret
 
 RL11:   and edx, 1FFh
         shl edx, 5
         mov eax, ebx
-        test BYTE [esi-1], 4h   ; Flip Vertical
+        test BYTE [esi-1], 4h       ; Flip Vertical
         jz RL12
         mov eax, 28
         sub eax, ebx
 
 RL12:   mov ebp, DWORD [VRAM+edx+eax]
-        test BYTE [esi-1], 2h   ; Flip Horizontal
+        test BYTE [esi-1], 2h       ; Flip Horizontal
         jnz RL22
 
         mov cl, 8
@@ -273,7 +253,7 @@ RL1:    mov eax, ebp
         dec cl
         jnz RL1
         dec ch
-        jnz RL0
+        jnz RL_0
         ret
 
 RL22:   mov cl, 8
@@ -300,11 +280,11 @@ RL3:    mov eax, ebp
         dec cl
         jnz RL3
         dec ch
-        jnz RL0
+        jnz RL_0
         ret
 
-; * Renderiza uma linha
-; ***********************
+; * Render one line in front layer
+; **********************************
 render_background_layer2:
         movzx eax, BYTE [VDPR+9]
         add eax, DWORD [ScanLine]
@@ -323,12 +303,12 @@ RBL000: shr eax, 3
 
         mov eax, DWORD [ScanLine]
         shl eax, 10
-        mov edi, [esp+24]			; Param buffer (after one call instruction)
+        mov edi, [esp+24]               ; Param buffer (after one call instruction)
         add edi, eax
 
         mov DWORD [scrollx], 0
 
-        ; Ocuta as duas primeiras linhas
+        ; Hide first two lines
         test BYTE [VDPR+0], 40h
         jz RBL00
         cmp DWORD [ScanLine], 16
@@ -344,33 +324,30 @@ RBL01:  movzx ebx, BYTE [VDPR+9]
         shl ebx, 2
 
         mov ch, 32
-RBL0:;  cmp ch, 8
-;       jne RL_0
-;       mov esi, scrolly
 RBL_0:  movzx edx, WORD [esi]
         add esi, 2
 
-        test BYTE [esi-1], 10h  ; Tile na frente do sprite (renderiza depois)
+        test BYTE [esi-1], 10h          ; Tile in front layer (renders now)
         jnz RBL_00
         add DWORD [scrollx], 8*4
         and DWORD [scrollx], 3FFh
         dec ch
-        jnz RBL0
+        jnz RBL_0
         ret
 
 RBL_00: and edx, 1FFh
         shl edx, 5
         mov eax, ebx
-        test BYTE [esi-1], 4h   ; Flip Vertical
+        test BYTE [esi-1], 4h           ; Flip Vertical
         jz RBL11
         mov eax, 28
         sub eax, ebx
 RBL11:  mov DWORD [pal], 0
-        test BYTE [esi-1], 8h   ; Usar palheta de sprite
+        test BYTE [esi-1], 8h           ; Sprite palette
         jz RBL12
         mov DWORD [pal], 16
 RBL12:  mov ebp, DWORD [VRAM+edx+eax]
-        test BYTE [esi-1], 2h   ; Flip Horizontal
+        test BYTE [esi-1], 2h           ; Flip Horizontal
         jnz RBL22
 
         mov cl, 8
@@ -401,7 +378,7 @@ RBL14:  add edx, 4
         dec cl
         jnz RBL1
         dec ch
-        jnz RBL0
+        jnz RBL_0
         ret
 
 RBL22:  mov cl, 8
@@ -431,11 +408,11 @@ RBL5:   add edx, 4
         dec cl
         jnz RBL3
         dec ch
-        jnz RBL0
+        jnz RBL_0
         ret
 
-; * Renderiza uma linha da camada de sprite
-; *******************************************
+; * Render one sprite line
+; **************************
 render_sprite_layer:
         xor ecx, ecx
         mov esi, VRAM + 3F00h
@@ -461,7 +438,7 @@ RSL00:  mov DWORD [sb], 0
 
 RSL01:  mov eax, DWORD [ScanLine]
         shl eax, 10
-        mov edi, [esp+24]			; Param buffer (after one call instruction)
+        mov edi, [esp+24]               ; Param buffer (after one call instruction)
         add edi, eax
         mov DWORD [vb], edi
 
@@ -471,8 +448,6 @@ RSL01:  mov eax, DWORD [ScanLine]
 
 RSL0:   mov al, BYTE [sl]
         mov ah, [esi+ecx]
-;       cmp ah, 208
-;       je RSL2
         sub al, ah
         cmp al, BYTE [s8x]
         jae RSL1
@@ -516,8 +491,6 @@ RSL4:   add edi, 4
 
 RSL1:   dec cl
         jnl RSL0
-;       cmp cl, 64
-;       jb RSL0
 RSL2:   ret
 
 
@@ -537,16 +510,14 @@ palette:
 SECTION .bss
 
 scrollx     RESD 1
-;scrolly        RESD 1
 pal         RESD 1
 vb          RESD 1
 sl          RESB 1
-;sl2            RESD 1
 sb          RESD 1
 s8x         RESB 1
 RenderBL2   RESB 1
 
 GLOBAL ScanLine, LineInt, VDPCounter
-ScanLine    RESD 1          ; Scanline atual
-LineInt     RESB 1          ; Line Interrupt pendente
+ScanLine    RESD 1          ; Current scanline
+LineInt     RESB 1          ; Line Interrupt pending
 VDPCounter  RESB 1          ; Line Interrupt Counter