diff --git a/zsnes/src/gui/gui.asm b/zsnes/src/gui/gui.asm
index f47ceeaf..1b632fbe 100644
--- a/zsnes/src/gui/gui.asm
+++ b/zsnes/src/gui/gui.asm
@@ -597,6 +597,8 @@ NEWSYM AutoIncSaveSlot, db 0
 NEWSYM TCPIPAddress, db 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
 NEWSYM SoundInterpType, db 2
 NEWSYM KeyDisplayFPS, dd 0
+NEWSYM KeyIncStateSlot, dd 0
+NEWSYM KeyDecStateSlot, dd 0
 
 GUIsave equ $-GUIRAdd
 
@@ -617,9 +619,9 @@ ModemPTimer  dd 0       ; Timer for modem process
 ModemOKStat  db 0       ; OK is detected on modem status
 
 ;                LOAD STAT INPT OPT  VID  SND  CHT  NET  GMKEY GUIOP ABT  RSET SRC  STCN MOVE CMBO ADDO
-GUIwinposxo dd 0,5   ,60  ,30  ,55  ,50  ,35  ,5   ,30  ,20   ,10   ,80  ,65  ,20  ,70  ,50  ,3   ,50
+GUIwinposxo dd 0,5   ,60  ,30  ,55  ,50  ,35  ,5   ,30  ,10   ,10   ,80  ,65  ,20  ,70  ,50  ,3   ,50
 GUIwinposyo dd 0,20  ,70  ,30  ,20  ,20  ,20  ,20  ,30  ,20   ,20   ,50  ,60  ,30  ,65  ,50  ,22  ,60
-GUIwinsizex dd 0,244 ,126 ,189 ,167 ,170 ,188 ,244 ,8*16,224  ,240  ,7*16,9*16,8*16,9*16,140 ,250 ,160
+GUIwinsizex dd 0,244 ,126 ,189 ,167 ,170 ,188 ,244 ,8*16,235  ,240  ,7*16,9*16,8*16,9*16,140 ,250 ,160
 GUIwinsizey dd 0,190 ,3*16,166 ,190 ,192 ,184 ,191 ,40  ,189  ,192  ,108  ,42  ,40  ,42  ,70  ,190 ,60
 GUIwinptr   db 0
 
diff --git a/zsnes/src/gui/guimouse.inc b/zsnes/src/gui/guimouse.inc
index eb9646cb..af7f62e8 100644
--- a/zsnes/src/gui/guimouse.inc
+++ b/zsnes/src/gui/guimouse.inc
@@ -2712,10 +2712,12 @@ DisplayGameOptnsClick:
     DGOptnsProcBox 27+45*3,120,[KeyDisableSC7]
     DGOptnsProcBox 27+45*2,132,[KeyStateSlc0]
     DGOptnsProcBox 27+45*3,132,[KeyStateSlc1]
+    DGOptnsProcBox 27+45*4,132,[KeyIncStateSlot]
     DGOptnsProcBox 27,140,[KeyStateSlc2]
     DGOptnsProcBox 27+45,140,[KeyStateSlc3]
     DGOptnsProcBox 27+45*2,140,[KeyStateSlc4]
     DGOptnsProcBox 27+45*3,140,[KeyStateSlc5]
+    DGOptnsProcBox 27+45*4,140,[KeyDecStateSlot]
     DGOptnsProcBox 27,148,[KeyStateSlc6]
     DGOptnsProcBox 27+45,148,[KeyStateSlc7]
     DGOptnsProcBox 27+45*2,148,[KeyStateSlc8]
diff --git a/zsnes/src/gui/guiwindp.inc b/zsnes/src/gui/guiwindp.inc
index 0339df39..4d368f5a 100644
--- a/zsnes/src/gui/guiwindp.inc
+++ b/zsnes/src/gui/guiwindp.inc
@@ -4482,6 +4482,7 @@ DisplayGameOptns:
     GUIOuttextwin2 9,9+45*2,134,GUIGameOptnsText7
     mov byte[GUIGameOptnsText7+2],'1'
     GUIOuttextwin2 9,9+45*3,134,GUIGameOptnsText7
+    GUIOuttextwin2 9,9+45*4,134,GUIGameOptnsTextY
     mov byte[GUIGameOptnsText7+2],'2'
     GUIOuttextwin2 9,9,141,GUIGameOptnsText7
     mov byte[GUIGameOptnsText7+2],'3'
@@ -4490,6 +4491,7 @@ DisplayGameOptns:
     GUIOuttextwin2 9,9+45*2,142,GUIGameOptnsText7
     mov byte[GUIGameOptnsText7+2],'5'
     GUIOuttextwin2 9,9+45*3,142,GUIGameOptnsText7
+    GUIOuttextwin2 9,9+45*4,142,GUIGameOptnsTextZ
     mov byte[GUIGameOptnsText7+2],'6'
     GUIOuttextwin2 9,9,150,GUIGameOptnsText7
     mov byte[GUIGameOptnsText7+2],'7'
@@ -4588,6 +4590,7 @@ DisplayGameOptns:
     GUIOuttextwin2 9,8+45*2,133,GUIGameOptnsText7
     mov byte[GUIGameOptnsText7+2],'1'
     GUIOuttextwin2 9,8+45*3,133,GUIGameOptnsText7
+    GUIOuttextwin2 9,8+45*4,133,GUIGameOptnsTextY
     mov byte[GUIGameOptnsText7+2],'2'
     GUIOuttextwin2 9,8,141,GUIGameOptnsText7
     mov byte[GUIGameOptnsText7+2],'3'
@@ -4596,6 +4599,7 @@ DisplayGameOptns:
     GUIOuttextwin2 9,8+45*2,141,GUIGameOptnsText7
     mov byte[GUIGameOptnsText7+2],'5'
     GUIOuttextwin2 9,8+45*3,141,GUIGameOptnsText7
+    GUIOuttextwin2 9,8+45*4,141,GUIGameOptnsTextZ
     mov byte[GUIGameOptnsText7+2],'6'
     GUIOuttextwin2 9,8,149,GUIGameOptnsText7
     mov byte[GUIGameOptnsText7+2],'7'
@@ -4654,10 +4658,12 @@ DisplayGameOptns:
     DGOptnsDrawBox 27+45*3,120,[KeyDisableSC7]
     DGOptnsDrawBox 27+45*2,132,[KeyStateSlc0]
     DGOptnsDrawBox 27+45*3,132,[KeyStateSlc1]
+    DGOptnsDrawBox 27+45*4,132,[KeyIncStateSlot]
     DGOptnsDrawBox 27,140,[KeyStateSlc2]
     DGOptnsDrawBox 27+45,140,[KeyStateSlc3]
     DGOptnsDrawBox 27+45*2,140,[KeyStateSlc4]
     DGOptnsDrawBox 27+45*3,140,[KeyStateSlc5]
+    DGOptnsDrawBox 27+45*4,140,[KeyDecStateSlot]
     DGOptnsDrawBox 27,148,[KeyStateSlc6]
     DGOptnsDrawBox 27+45,148,[KeyStateSlc7]
     DGOptnsDrawBox 27+45*2,148,[KeyStateSlc8]
@@ -4709,6 +4715,8 @@ GUIGameOptnsTextT db 'SLOWDWN KEY',0
 GUIGameOptnsTextU db 'CLOCK',0
 GUIGameOptnsTextV db 'SAVE SPC',0
 GUIGameOptnsTextX db 'DISPLAY FPS',0
+GUIGameOptnsTextY db 'ST+',0
+GUIGameOptnsTextZ db 'ST-',0
 
 DisplayGUIOptns:
     GUIDrawWindowBox 10,GUIGUIDisp
diff --git a/zsnes/src/vcache.asm b/zsnes/src/vcache.asm
index 7c9c91e3..a2e1536b 100644
--- a/zsnes/src/vcache.asm
+++ b/zsnes/src/vcache.asm
@@ -33,6 +33,7 @@ EXTSYM KeyBGDisble0,KeyBGDisble1,KeyBGDisble2,KeyBGDisble3,KeySprDisble
 EXTSYM KeyResetAll,KeyExtraEnab,KeyWinDisble,KeyNewGfxSwt,KeyOffsetMSw
 EXTSYM KeyStateSlc0,KeyStateSlc1,KeyStateSlc2,KeyStateSlc3,KeyStateSlc4
 EXTSYM KeyStateSlc5,KeyStateSlc6,KeyStateSlc7,KeyStateSlc8,KeyStateSlc9
+EXTSYM KeyIncStateSlot,KeyDecStateSlot
 EXTSYM maxskip,DSPMem,SprValAdd,dsp1ptr,dsp1array,FastFwdToggle,SaveSramData
 EXTSYM ngextbg,Mode7HiRes,Check60hz,Get_MouseData,Get_MousePositionDisplacement
 EXTSYM WindowDisables,scanlines,romispal
@@ -723,6 +724,94 @@ NEWSYM cachevideo
     soundselcomp KeyDisableSC5,Voice5Disable,Voice5Status,'6'
     soundselcomp KeyDisableSC6,Voice6Disable,Voice6Status,'7'
     soundselcomp KeyDisableSC7,Voice7Disable,Voice7Status,'8'
+
+    mov eax,[KeyIncStateSlot]
+    test byte[pressed+eax],1
+    je .noincstateslot
+    mov byte[pressed+eax],2
+    mov eax,[statefileloc]
+    mov dh,[fnamest+eax]
+%ifndef __LINUX__
+    cmp dh,'T'
+%else
+    cmp dh,'t'
+%endif
+    je .secondstate
+    cmp dh,'9'
+    je .jumptofirststate
+    inc dh
+    jmp .donextstate
+.secondstate
+    mov dh,'1'
+    jmp .donextstate
+.jumptofirststate
+%ifndef __LINUX__
+    mov dh,'T'
+%else
+    mov dh,'t'
+%endif
+.donextstate
+    mov byte[fnamest+eax],dh
+%ifndef __LINUX__
+    cmp dh,'T'
+%else
+    cmp dh,'t'
+%endif
+    je .firststatemsg
+    mov byte[sselm+11],dh
+    jmp .incstatemsg
+.firststatemsg
+    mov byte[sselm+11],'0'
+.incstatemsg
+    mov dword[Msgptr],sselm
+    mov eax,[MsgCount]
+    mov [MessageOn],eax
+    xor dh,dh
+.noincstateslot
+
+    mov eax,[KeyDecStateSlot]
+    test byte[pressed+eax],1
+    je .nodecstateslot
+    mov byte[pressed+eax],2
+    mov eax,[statefileloc]
+    mov dh,[fnamest+eax]
+%ifndef __LINUX__
+    cmp dh,'T'
+%else
+    cmp dh,'t'
+%endif
+    je .jumptolaststate
+    dec dh
+    cmp dh,'0'
+    jne .doprevstate
+.firststate
+%ifndef __LINUX__
+    mov dh,'T'
+%else
+    mov dh,'t'
+%endif
+    jmp .doprevstate
+.jumptolaststate
+    mov dh,'9'
+.doprevstate
+    mov byte[fnamest+eax],dh
+%ifndef __LINUX__
+    cmp dh,'T'
+%else
+    cmp dh,'t'
+%endif
+    je .firststatemsg2
+    mov byte[sselm+11],dh
+    jmp .decstatemsg
+.firststatemsg2
+    mov byte[sselm+11],'0'
+.decstatemsg
+    mov dword[Msgptr],sselm
+    mov eax,[MsgCount]
+    mov [MessageOn],eax
+    xor dh,dh
+.nodecstateslot
+
 .finishchatskip
     cmp byte[curblank],0h
     jne near yesblank