pagetable lab initialized

kernel/uart.c

@@ -13,7 +13,7 @@
 // the UART control registers are memory-mapped
 // at address UART0. this macro returns the
 // address of one of the registers.
-#define Reg(reg) ((volatile unsigned char *)(UART0 + reg))
+#define Reg(reg) ((volatile unsigned char *)(UART0 + (reg)))
 
 // the UART control registers.
 // some have different meanings for
@@ -136,6 +136,7 @@ uartstart()
   while(1){
     if(uart_tx_w == uart_tx_r){
       // transmit buffer is empty.
+      ReadReg(ISR);
       return;
     }