diff --git a/src/libsys/console.c b/src/libsys/console.c
index e03f546..8209bd6 100644
--- a/src/libsys/console.c
+++ b/src/libsys/console.c
@@ -8,7 +8,7 @@
 #include <string.h>
 #include "console.h"
 
-extern con_if_t con_if;
+extern const con_if_t con_if;
 
 // Funcs
 con_if_entry_t const* con_getInterface(int file)
@@ -94,24 +94,25 @@ void con_flush(int fd)
 
 int con_readchar(con_if_entry_t const *pIF)
 {
-	int c;
-	assert(pIF);
-
-	// busy read
-	do
+	int c = -1;
+	if (pIF)
 	{
-		c = pIF->readchar(pIF->pInst);
-		
-	} while(c < 0);
-	
+		// busy read
+		do
+		{
+			c = pIF->readchar(pIF->pInst);
+
+		} while(c < 0);
+	}	
 	return c;
 }
 
 void con_writechar(con_if_entry_t const *pIF, char c)
 {
-	assert(pIF);
-
-	pIF->writechar(pIF->pInst, c);
+	if (pIF)
+	{
+		pIF->writechar(pIF->pInst, c);
+	}
 }
 
 // ---------------------------------------------------------------------------------
diff --git a/src/libsys/uart.c b/src/libsys/uart.c
index 45cdd30..cc97b08 100644
--- a/src/libsys/uart.c
+++ b/src/libsys/uart.c
@@ -12,28 +12,32 @@
 // ------------------------------------
 void UART_setbaud(void const *pInst, uint32_t baudrate)
 {
-	uart_if_t *pReg = (uart_if_t*)pInst;
-
-	*pReg->pBAUD = UART_CALC_BAUD(baudrate);
+	if (pInst)
+	{
+		uart_if_t *pReg = (uart_if_t*)pInst;
+		*pReg->pBAUD = UART_CALC_BAUD(baudrate);
+	}
 }
 
 int UART_readchar(void const *pInst)
 {
-	uart_if_t *pReg = (uart_if_t*)pInst;
-
-	if (SYS_UART_BIT_RX_AVAIL & *pReg->pCTRL)
+	if (pInst)
 	{
-		return (*pReg->pDATA & 0xFF);
+		uart_if_t *pReg = (uart_if_t*)pInst;
+		if (SYS_UART_BIT_RX_AVAIL & *pReg->pCTRL)
+		{
+			return (*pReg->pDATA & 0xFF);
+		}
 	}
-
 	return -1;
 }
 
 void UART_writechar(void const *pInst, char c)
 {
-	uart_if_t *pReg = (uart_if_t*)pInst;
-
-	while((SYS_UART_BIT_TX_HALFFULL & *pReg->pCTRL) != 0);
-
-	*pReg->pDATA = (uint32_t)c;
+	if (pInst)
+	{
+		uart_if_t *pReg = (uart_if_t*)pInst;
+		while((SYS_UART_BIT_TX_HALFFULL & *pReg->pCTRL) != 0);
+		*pReg->pDATA = (uint32_t)c;
+	}
 }