diff --git a/radio/src/lua_api.cpp b/radio/src/lua_api.cpp
index 5f8b06e09..174d1a522 100644
--- a/radio/src/lua_api.cpp
+++ b/radio/src/lua_api.cpp
@@ -614,7 +614,7 @@ static int luaModelSetInfo(lua_State *L)
 
 static int luaModelGetTimer(lua_State *L)
 {
-  int idx = luaL_checkunsigned(L, 1);
+  unsigned int idx = luaL_checkunsigned(L, 1);
   if (idx < MAX_TIMERS) {
     TimerData & timer = g_model.timers[idx];
     lua_newtable(L);
@@ -633,7 +633,7 @@ static int luaModelGetTimer(lua_State *L)
 
 static int luaModelSetTimer(lua_State *L)
 {
-  int idx = luaL_checkunsigned(L, 1);
+  unsigned int idx = luaL_checkunsigned(L, 1);
 
   if (idx < MAX_TIMERS) {
     TimerData & timer = g_model.timers[idx];
@@ -667,47 +667,43 @@ static int luaModelSetTimer(lua_State *L)
 
 static int luaModelResetTimer(lua_State *L)
 {
-  int idx = luaL_checkunsigned(L, 1);
+  unsigned int idx = luaL_checkunsigned(L, 1);
   if (idx < MAX_TIMERS) {
     timerReset(idx);
   }
   return 0;
 }
 
-static int getFirstInput(int chn)
+static unsigned int getFirstInput(unsigned int chn)
 {
-  for (int i=0; i<MAX_INPUTS; i++) {
+  for (unsigned int i=0; i<MAX_INPUTS; i++) {
     ExpoData * expo = expoAddress(i);
-    if (!expo->srcRaw || expo->chn>chn) break;
-    if (expo->chn == chn) {
+    if (!expo->srcRaw || expo->chn >= chn) {
       return i;
     }
   }
-  return -1;
+  return 0;
 }
 
-static int getInputsCountFromFirst(int chn, int first)
+static unsigned int getInputsCountFromFirst(unsigned int chn, unsigned int first)
 {
-  int count = 0;
-  if (first >= 0) {
-    for (int i=first; i<MAX_INPUTS; i++) {
-      ExpoData * expo = expoAddress(i);
-      if (!expo->srcRaw || expo->chn!=chn) break;
-      count++;
-    }
+  unsigned int count = 0;
+  for (unsigned int i=first; i<MAX_INPUTS; i++) {
+    ExpoData * expo = expoAddress(i);
+    if (!expo->srcRaw || expo->chn!=chn) break;
+    count++;
   }
   return count;
 }
 
-static int getInputsCount(int chn)
+static unsigned int getInputsCount(unsigned int chn)
 {
-  int first = getFirstInput(chn);
-  return getInputsCountFromFirst(chn, first);
+  return getInputsCountFromFirst(chn, getFirstInput(chn));
 }
 
 static int luaModelGetInputsCount(lua_State *L)
 {
-  int chn = luaL_checkunsigned(L, 1);
+  unsigned int chn = luaL_checkunsigned(L, 1);
   int count = getInputsCount(chn);
   lua_pushinteger(L, count);
   return 1;
@@ -715,11 +711,11 @@ static int luaModelGetInputsCount(lua_State *L)
 
 static int luaModelGetInput(lua_State *L)
 {
-  int chn = luaL_checkunsigned(L, 1);
-  int idx = luaL_checkunsigned(L, 2);
-  int first = getFirstInput(chn);
-  int count = getInputsCountFromFirst(chn, first);
-  if (first>=0 && idx<count) {
+  unsigned int chn = luaL_checkunsigned(L, 1);
+  unsigned int idx = luaL_checkunsigned(L, 2);
+  unsigned int first = getFirstInput(chn);
+  unsigned int count = getInputsCountFromFirst(chn, first);
+  if (count && (idx < count)) {
     ExpoData * expo = expoAddress(first+idx);
     lua_newtable(L);
     lua_pushtablezstring(L, "name", expo->name);
@@ -735,15 +731,15 @@ static int luaModelGetInput(lua_State *L)
 
 static int luaModelInsertInput(lua_State *L)
 {
-  int chn = luaL_checkunsigned(L, 1);
-  int idx = luaL_checkunsigned(L, 2);
+  unsigned int chn = luaL_checkunsigned(L, 1);
+  unsigned int idx = luaL_checkunsigned(L, 2);
 
-  int first = getFirstInput(chn);
-  int count = getInputsCountFromFirst(chn, first);
+  unsigned int first = getFirstInput(chn);
+  unsigned int count = getInputsCountFromFirst(chn, first);
 
   if (chn<MAX_INPUTS && getExpoMixCount(1)<MAX_INPUTS && idx<=count) {
-    idx = first+idx;
-    s_currCh = chn+1;
+    idx = first + idx;
+    s_currCh = chn + 1;
     insertExpoMix(1, idx);
     ExpoData * expo = expoAddress(idx);
     luaL_checktype(L, -1, LUA_TTABLE);
@@ -774,13 +770,13 @@ static int luaModelInsertInput(lua_State *L)
 
 static int luaModelDeleteInput(lua_State *L)
 {
-  int chn = luaL_checkunsigned(L, 1);
-  int idx = luaL_checkunsigned(L, 2);
+  unsigned int chn = luaL_checkunsigned(L, 1);
+  unsigned int idx = luaL_checkunsigned(L, 2);
 
   int first = getFirstInput(chn);
-  int count = getInputsCountFromFirst(chn, first);
+  unsigned int count = getInputsCountFromFirst(chn, first);
 
-  if (first>=0 && idx<count) {
+  if (count && (idx < count)) {
     deleteExpoMix(1, first+idx);
   }
 
@@ -831,7 +827,7 @@ static int getMixesCount(int chn)
 
 static int luaModelGetMixesCount(lua_State *L)
 {
-  int chn = luaL_checkunsigned(L, 1);
+  unsigned int chn = luaL_checkunsigned(L, 1);
   int count = getMixesCount(chn);
   lua_pushinteger(L, count);
   return 1;
@@ -839,11 +835,11 @@ static int luaModelGetMixesCount(lua_State *L)
 
 static int luaModelGetMix(lua_State *L)
 {
-  int chn = luaL_checkunsigned(L, 1);
-  int idx = luaL_checkunsigned(L, 2);
+  unsigned int chn = luaL_checkunsigned(L, 1);
+  unsigned int idx = luaL_checkunsigned(L, 2);
   int first = getFirstMix(chn);
-  int count = getMixesCountFromFirst(chn, first);
-  if (idx<count) {
+  unsigned int count = getMixesCountFromFirst(chn, first);
+  if (idx < count) {
     MixData * mix = mixAddress(first+idx);
     lua_newtable(L);
     lua_pushtablezstring(L, "name", mix->name);
@@ -870,11 +866,11 @@ static int luaModelGetMix(lua_State *L)
 
 static int luaModelInsertMix(lua_State *L)
 {
-  int chn = luaL_checkunsigned(L, 1);
-  int idx = luaL_checkunsigned(L, 2);
+  unsigned int chn = luaL_checkunsigned(L, 1);
+  unsigned int idx = luaL_checkunsigned(L, 2);
 
   int first = getFirstMix(chn);
-  int count = getMixesCountFromFirst(chn, first);
+  unsigned int count = getMixesCountFromFirst(chn, first);
 
   if (chn<NUM_CHNOUT && getExpoMixCount(0)<MAX_MIXERS && idx<=count) {
     idx += first;
@@ -939,13 +935,13 @@ static int luaModelInsertMix(lua_State *L)
 
 static int luaModelDeleteMix(lua_State *L)
 {
-  int chn = luaL_checkunsigned(L, 1);
-  int idx = luaL_checkunsigned(L, 2);
+  unsigned int chn = luaL_checkunsigned(L, 1);
+  unsigned int idx = luaL_checkunsigned(L, 2);
 
   int first = getFirstMix(chn);
-  int count = getMixesCountFromFirst(chn, first);
+  unsigned int count = getMixesCountFromFirst(chn, first);
 
-  if (idx<count) {
+  if (idx < count) {
     deleteExpoMix(0, first+idx);
   }
 
@@ -960,7 +956,7 @@ static int luaModelDeleteMixes(lua_State *L)
 
 static int luaModelGetLogicalSwitch(lua_State *L)
 {
-  int idx = luaL_checkunsigned(L, 1);
+  unsigned int idx = luaL_checkunsigned(L, 1);
   if (idx < NUM_LOGICAL_SWITCH) {
     LogicalSwitchData * sw = lswAddress(idx);
     lua_newtable(L);
@@ -980,7 +976,7 @@ static int luaModelGetLogicalSwitch(lua_State *L)
 
 static int luaModelSetLogicalSwitch(lua_State *L)
 {
-  int idx = luaL_checkunsigned(L, 1);
+  unsigned int idx = luaL_checkunsigned(L, 1);
   if (idx < NUM_LOGICAL_SWITCH) {
     LogicalSwitchData * sw = lswAddress(idx);
     memclear(sw, sizeof(LogicalSwitchData));
@@ -1018,7 +1014,7 @@ static int luaModelSetLogicalSwitch(lua_State *L)
 
 static int luaModelGetCurve(lua_State *L)
 {
-  int idx = luaL_checkunsigned(L, 1);
+  unsigned int idx = luaL_checkunsigned(L, 1);
   if (idx < MAX_CURVES) {
     CurveInfo & curveInfo = g_model.curves[idx];
     lua_newtable(L);
@@ -1060,7 +1056,7 @@ static int luaModelGetCurve(lua_State *L)
 
 static int luaModelGetCustomFunction(lua_State *L)
 {
-  int idx = luaL_checkunsigned(L, 1);
+  unsigned int idx = luaL_checkunsigned(L, 1);
   if (idx < NUM_CFN) {
     CustomFunctionData * cfn = &g_model.customFn[idx];
     lua_newtable(L);
@@ -1084,7 +1080,7 @@ static int luaModelGetCustomFunction(lua_State *L)
 
 static int luaModelSetCustomFunction(lua_State *L)
 {
-  int idx = luaL_checkunsigned(L, 1);
+  unsigned int idx = luaL_checkunsigned(L, 1);
   if (idx < NUM_CFN) {
     CustomFunctionData * cfn = &g_model.customFn[idx];
     memclear(cfn, sizeof(CustomFunctionData));
@@ -1123,7 +1119,7 @@ static int luaModelSetCustomFunction(lua_State *L)
 
 static int luaModelGetOutput(lua_State *L)
 {
-  int idx = luaL_checkunsigned(L, 1);
+  unsigned int idx = luaL_checkunsigned(L, 1);
   if (idx < NUM_CHNOUT) {
     LimitData * limit = limitAddress(idx);
     lua_newtable(L);
@@ -1147,7 +1143,7 @@ static int luaModelGetOutput(lua_State *L)
 
 static int luaModelSetOutput(lua_State *L)
 {
-  int idx = luaL_checkunsigned(L, 1);
+  unsigned int idx = luaL_checkunsigned(L, 1);
   if (idx < NUM_CHNOUT) {
     LimitData * limit = limitAddress(idx);
     luaL_checktype(L, -1, LUA_TTABLE);
@@ -1191,8 +1187,8 @@ static int luaModelSetOutput(lua_State *L)
 
 static int luaModelGetGlobalVariable(lua_State *L)
 {
-  int idx = luaL_checkunsigned(L, 1);
-  int phase = luaL_checkunsigned(L, 2);
+  unsigned int idx = luaL_checkunsigned(L, 1);
+  unsigned int phase = luaL_checkunsigned(L, 2);
   if (phase < MAX_FLIGHT_MODES && idx < MAX_GVARS)
     lua_pushinteger(L, g_model.flightModeData[phase].gvars[idx]);
   else
@@ -1202,8 +1198,8 @@ static int luaModelGetGlobalVariable(lua_State *L)
 
 static int luaModelSetGlobalVariable(lua_State *L)
 {
-  int idx = luaL_checkunsigned(L, 1);
-  int phase = luaL_checkunsigned(L, 2);
+  unsigned int idx = luaL_checkunsigned(L, 1);
+  unsigned int phase = luaL_checkunsigned(L, 2);
   int value = luaL_checkinteger(L, 3);
   if (phase < MAX_FLIGHT_MODES && idx < MAX_GVARS && value >= -GVAR_MAX && value <= GVAR_MAX) {
     g_model.flightModeData[phase].gvars[idx] = value;