diff --git a/src/libsys/boards/denano/board.c b/src/libsys/boards/denano/board.c
index dd5bbb2..b6fb7d7 100644
--- a/src/libsys/boards/denano/board.c
+++ b/src/libsys/boards/denano/board.c
@@ -26,6 +26,8 @@ con_if_t con_if =
 	con_if_entry, ARRAYSIZE(con_if_entry)
 };
 
+uart_if_t const *dbg_uart = NULL;
+
 void dbg_uart_setup();
 
 void board_init(void)
@@ -54,44 +56,53 @@ extern void dbg_handler(struct xcptcontext * xcp);
 void dbg_uart_isr(struct xcptcontext *xcp);
 void dbg_uart_setup()
 {
-	uart_if_t *pUart = (uart_if_t*)con_getInstanceByName("UART-1");
+	const int UART_INT = SYS_INT_UART1;
+	dbg_uart = (uart_if_t*)con_getInterfaceByName("UART-1")->pInst;
 	
-	*pUart->pCTRL = SYS_UART_BIT_RX_INTEN;
-	interrupt_register(SYS_INT_UART1, dbg_uart_isr);
-	interrupt_enable(SYS_INT_UART1);
+	*dbg_uart->pCTRL = SYS_UART_BIT_RX_INTEN;
+	interrupt_register(UART_INT, dbg_uart_isr);
+	interrupt_enable(UART_INT);
 }
 
 void dbg_uart_isr(struct xcptcontext *xcp)
 {
-	uart_if_t *pUart = (uart_if_t*)con_getInstanceByName("UART-1");
-
-	if(SYS_UART_BIT_RX_AVAIL & *pUart->pCTRL)
+	if(SYS_UART_BIT_RX_AVAIL & *dbg_uart->pCTRL)
 	{
-		char c = *pUart->pDATA;
+		char c = *dbg_uart->pDATA;
 		if (c == 3)
 		{
-			// Disable UART interrupt 
-			// to prevent consuming uart data in ISR during single step
-			// Interrupts mask bits are recovered on return from exception 
-			//interrupt_disable(SYS_INT_UART1);
-			//uint32_t im = 1 << SYS_INT_UART1;
-			//xcp->sr &= ~(SR_MASK_IM & (im << 8));
-			//*pUart->pCTRL &= ~SYS_UART_BIT_RX_INTEN;
 			dbg_handler(xcp);
 		}
 	}
 }
+
+inline void _dbg_writechar(uart_if_t const *pUart, char c)
+{
+	while((SYS_UART_BIT_TX_HALFFULL & *pUart->pCTRL) != 0);
+
+	*pUart->pDATA = (uint32_t)c;
 	
+}
+
+inline char _dbg_readchar(uart_if_t const *pUart)
+{
+	// busy read
+	while(!(SYS_UART_BIT_RX_AVAIL & *pUart->pCTRL));
+
+	return (*pUart->pDATA & 0xFF);
+
+}
+
 void dbg_putchar(char c)
 {
 	if (c == 0x0A)
 	{
-		writechar(4, 0x0D);
+		_dbg_writechar(dbg_uart, 0x0D);
 	}
-	writechar(4, c);
+	_dbg_writechar(dbg_uart, c);
 }
 
 char dbg_getchar()
 {
-	return (char)readchar(4);
+	return (char)_dbg_readchar(dbg_uart);
 }
diff --git a/src/libsys/console.c b/src/libsys/console.c
index 8265082..e03f546 100644
--- a/src/libsys/console.c
+++ b/src/libsys/console.c
@@ -26,6 +26,21 @@ con_if_entry_t const* con_getInterface(int file)
 	return result;
 }
 
+con_if_entry_t const* con_getInterfaceByName(char const *pName)
+{
+	void const *result = NULL;
+	int i;
+	for (i=0; i < con_if.length; i++)
+	{
+		if (!strcmp(pName, con_if.con_if_entry[i].pName))
+		{
+			result = &con_if.con_if_entry[i];
+			break;
+		}
+	}
+	return result;
+}
+
 void const* con_getInstanceByName(char const *pName)
 {
 	void const *result = NULL;
@@ -77,12 +92,9 @@ void con_flush(int fd)
 	} while(c > 0);
 }
 
-// ---------------------------------------------------------------------------------
-int readchar(int fd)
+int con_readchar(con_if_entry_t const *pIF)
 {
 	int c;
-	con_if_entry_t const *pIF = con_getInterface(fd);
-	
 	assert(pIF);
 
 	// busy read
@@ -95,26 +107,31 @@ int readchar(int fd)
 	return c;
 }
 
-void writechar(int fd, char c)
+void con_writechar(con_if_entry_t const *pIF, char c)
 {
-	con_if_entry_t const *pIF = con_getInterface(fd);
-
 	assert(pIF);
 
 	pIF->writechar(pIF->pInst, c);
-	
+}
+
+// ---------------------------------------------------------------------------------
+int readchar(int fd)
+{
+	return con_readchar(con_getInterface(fd));
+}
+
+void writechar(int fd, char c)
+{
+	con_writechar(con_getInterface(fd), c);
 }
 
 void _putchar(int fd, char c)
 {
-	con_if_entry_t const *pIF = con_getInterface(fd);
-
-	assert(pIF);
 	if (c == 0x0A)
 	{
-		pIF->writechar(pIF->pInst, 0x0D);
+		writechar(fd, 0x0D);
 	}
-	pIF->writechar(pIF->pInst, c);
+	writechar(fd, c);
 
 }
 
diff --git a/src/libsys/console.h b/src/libsys/console.h
index 80fd72b..20d9226 100644
--- a/src/libsys/console.h
+++ b/src/libsys/console.h
@@ -50,7 +50,10 @@ int con_open(char const *pName);
 int con_close(int fd);
 void con_flush(int file);
 con_if_entry_t const* con_getInterface(int file);
+con_if_entry_t const* con_getInterfaceByName(char const *pName);
 void const* con_getInstanceByName(char const *pName);
+int con_readchar(con_if_entry_t const *pIF);
+void con_writechar(con_if_entry_t const *pIF, char c);
 
 int readchar(int file);
 void writechar(int file, char c);