diff --git a/demos/host/host_os_none/host_os_none.uvopt b/demos/host/host_os_none/host_os_none.uvopt
index d54fd60d0..083fddd67 100644
--- a/demos/host/host_os_none/host_os_none.uvopt
+++ b/demos/host/host_os_none/host_os_none.uvopt
@@ -73,7 +73,7 @@
       <OPTFL>
         <tvExp>1</tvExp>
         <tvExpOptDlg>0</tvExpOptDlg>
-        <IsCurrentTarget>0</IsCurrentTarget>
+        <IsCurrentTarget>1</IsCurrentTarget>
       </OPTFL>
       <CpuCode>8</CpuCode>
       <Books>
@@ -465,7 +465,7 @@
       <OPTFL>
         <tvExp>1</tvExp>
         <tvExpOptDlg>0</tvExpOptDlg>
-        <IsCurrentTarget>1</IsCurrentTarget>
+        <IsCurrentTarget>0</IsCurrentTarget>
       </OPTFL>
       <CpuCode>8</CpuCode>
       <Books>
@@ -928,10 +928,10 @@
       <FileType>1</FileType>
       <tvExp>0</tvExp>
       <Focus>0</Focus>
-      <ColumnNumber>1</ColumnNumber>
+      <ColumnNumber>0</ColumnNumber>
       <tvExpOptDlg>0</tvExpOptDlg>
-      <TopLine>122</TopLine>
-      <CurrentLine>142</CurrentLine>
+      <TopLine>1</TopLine>
+      <CurrentLine>1</CurrentLine>
       <bDave2>0</bDave2>
       <PathWithFileName>..\src\msc_app.c</PathWithFileName>
       <FilenameWithoutPath>msc_app.c</FilenameWithoutPath>
@@ -1018,8 +1018,8 @@
       <Focus>0</Focus>
       <ColumnNumber>0</ColumnNumber>
       <tvExpOptDlg>0</tvExpOptDlg>
-      <TopLine>147</TopLine>
-      <CurrentLine>166</CurrentLine>
+      <TopLine>1</TopLine>
+      <CurrentLine>1</CurrentLine>
       <bDave2>0</bDave2>
       <PathWithFileName>..\..\..\tinyusb\host\hub.c</PathWithFileName>
       <FilenameWithoutPath>hub.c</FilenameWithoutPath>
@@ -1112,10 +1112,10 @@
       <FileType>1</FileType>
       <tvExp>0</tvExp>
       <Focus>0</Focus>
-      <ColumnNumber>17</ColumnNumber>
+      <ColumnNumber>0</ColumnNumber>
       <tvExpOptDlg>0</tvExpOptDlg>
       <TopLine>32</TopLine>
-      <CurrentLine>45</CurrentLine>
+      <CurrentLine>38</CurrentLine>
       <bDave2>0</bDave2>
       <PathWithFileName>..\..\..\tinyusb\hal\hal_lpc175x_6x.c</PathWithFileName>
       <FilenameWithoutPath>hal_lpc175x_6x.c</FilenameWithoutPath>
@@ -1162,7 +1162,7 @@
       <Focus>0</Focus>
       <ColumnNumber>0</ColumnNumber>
       <tvExpOptDlg>0</tvExpOptDlg>
-      <TopLine>1</TopLine>
+      <TopLine>15</TopLine>
       <CurrentLine>34</CurrentLine>
       <bDave2>0</bDave2>
       <PathWithFileName>..\..\..\tinyusb\class\cdc_host.c</PathWithFileName>
@@ -1304,10 +1304,10 @@
       <FileType>1</FileType>
       <tvExp>0</tvExp>
       <Focus>0</Focus>
-      <ColumnNumber>63</ColumnNumber>
+      <ColumnNumber>15</ColumnNumber>
       <tvExpOptDlg>0</tvExpOptDlg>
-      <TopLine>584</TopLine>
-      <CurrentLine>605</CurrentLine>
+      <TopLine>3</TopLine>
+      <CurrentLine>10</CurrentLine>
       <bDave2>0</bDave2>
       <PathWithFileName>..\..\..\tinyusb\host\ohci\ohci.c</PathWithFileName>
       <FilenameWithoutPath>ohci.c</FilenameWithoutPath>
@@ -1726,7 +1726,7 @@
 
   <Group>
     <GroupName>bsp lpc175x_6x</GroupName>
-    <tvExp>1</tvExp>
+    <tvExp>0</tvExp>
     <tvExpOptDlg>0</tvExpOptDlg>
     <cbSel>0</cbSel>
     <RteFlg>0</RteFlg>
@@ -1752,10 +1752,10 @@
       <FileType>1</FileType>
       <tvExp>0</tvExp>
       <Focus>0</Focus>
-      <ColumnNumber>0</ColumnNumber>
+      <ColumnNumber>35</ColumnNumber>
       <tvExpOptDlg>0</tvExpOptDlg>
-      <TopLine>0</TopLine>
-      <CurrentLine>0</CurrentLine>
+      <TopLine>74</TopLine>
+      <CurrentLine>86</CurrentLine>
       <bDave2>0</bDave2>
       <PathWithFileName>..\..\..\mcu\lpc175x_6x\LPC17xx_DriverLib\source\lpc17xx_clkpwr.c</PathWithFileName>
       <FilenameWithoutPath>lpc17xx_clkpwr.c</FilenameWithoutPath>
diff --git a/demos/host/host_os_none/host_os_none.uvproj b/demos/host/host_os_none/host_os_none.uvproj
index 4e639ebf4..734b6bbf8 100644
--- a/demos/host/host_os_none/host_os_none.uvproj
+++ b/demos/host/host_os_none/host_os_none.uvproj
@@ -347,7 +347,7 @@
             <uThumb>0</uThumb>
             <uSurpInc>0</uSurpInc>
             <VariousControls>
-              <MiscControls>--gnu --c99 --diag_suppress=66</MiscControls>
+              <MiscControls>--gnu --c99</MiscControls>
               <Define>CORE_M4 TUSB_CFG_MCU=MCU_LPC43XX BOARD=BOARD_EA4357 TUSB_CFG_OS=TUSB_OS_NONE</Define>
               <Undefine></Undefine>
               <IncludePath>..\src;..\..\..\mcu\lpc43xx\CMSIS_LPC43xx_DriverLib\inc;..\..\..\boards;..\..\..\tinyusb;..\..\..\vendor\fatfs</IncludePath>
@@ -1877,7 +1877,7 @@
             <uThumb>0</uThumb>
             <uSurpInc>0</uSurpInc>
             <VariousControls>
-              <MiscControls>--gnu --c99 --diag_suppress=66</MiscControls>
+              <MiscControls>--gnu --c99</MiscControls>
               <Define>TUSB_CFG_MCU=MCU_LPC175X_6X BOARD=BOARD_LPCXPRESSO1769 TUSB_CFG_OS=TUSB_OS_NONE</Define>
               <Undefine></Undefine>
               <IncludePath>..\src;..\..\..\mcu\lpc175x_6x\CMSIS_CORE_LPC17xx\inc;..\..\..\mcu\lpc175x_6x\LPC17xx_DriverLib\include;..\..\..\boards;..\..\..\tinyusb;..\..\..\vendor\fatfs</IncludePath>
diff --git a/tinyusb/class/cdc_rndis.h b/tinyusb/class/cdc_rndis.h
index 33df6cf6b..c610e5781 100644
--- a/tinyusb/class/cdc_rndis.h
+++ b/tinyusb/class/cdc_rndis.h
@@ -51,6 +51,10 @@
  extern "C" {
 #endif
 
+#ifdef __CC_ARM
+#pragma diag_suppress 66 // Suppress Keil warnings #66-D: enumeration value is out of "int" range
+#endif
+
 /// RNDIS Message Types
 typedef enum {
   RNDIS_MSG_PACKET           = 0x00000001UL, ///< The host and device use this to send network data to one another.
@@ -85,6 +89,10 @@ typedef enum {
   RNDIS_STATUS_MEDIA_DISCONNECT = 0x4001000CUL  ///< Device is disconnected from the medium.
 }rndis_msg_status_t;
 
+#ifdef __CC_ARM
+#pragma diag_default 66 // return Keil 66 to normal severity
+#endif
+
 //--------------------------------------------------------------------+
 // MESSAGE STRUCTURE
 //--------------------------------------------------------------------+
diff --git a/tinyusb/hal/hal_lpc175x_6x.c b/tinyusb/hal/hal_lpc175x_6x.c
index c04b1660c..c611656a6 100644
--- a/tinyusb/hal/hal_lpc175x_6x.c
+++ b/tinyusb/hal/hal_lpc175x_6x.c
@@ -41,6 +41,10 @@
 
 #if TUSB_CFG_MCU == MCU_LPC175X_6X
 
+#ifdef __CC_ARM
+#pragma diag_suppress 66 // Suppress Keil warnings #66-D: enumeration value is out of "int" range
+#endif
+
 //--------------------------------------------------------------------+
 // IMPLEMENTATION
 //--------------------------------------------------------------------+
diff --git a/tinyusb/host/ohci/ohci.c b/tinyusb/host/ohci/ohci.c
index 63b30e0ac..5bd7db475 100644
--- a/tinyusb/host/ohci/ohci.c
+++ b/tinyusb/host/ohci/ohci.c
@@ -79,6 +79,10 @@ enum {
   OHCI_PERIODIC_START = 0x3E67
 };
 
+#ifdef __CC_ARM
+#pragma diag_suppress 66 // Suppress Keil warnings #66-D: enumeration value is out of "int" range
+#endif
+
 enum {
   OHCI_INT_SCHEDULING_OVERUN_MASK    = BIT_(0),
   OHCI_INT_WRITEBACK_DONEHEAD_MASK   = BIT_(1),
@@ -92,6 +96,10 @@ enum {
   OHCI_INT_MASTER_ENABLE_MASK        = BIT_(31),
 };
 
+#ifdef __CC_ARM
+#pragma diag_default 66 // return Keil 66 to normal severity
+#endif
+
 enum {
   OHCI_RHPORT_CURRENT_CONNECT_STATUS_MASK      = BIT_(0),
   OHCI_RHPORT_PORT_ENABLE_STATUS_MASK          = BIT_(1),