[SPCA] devices

semester3/spca/code-examples/03_hw/00_driver.c

@@ -0,0 +1,14 @@
+#define UART_BASE 0x3f8                     // Registers specified by 
+#define UART_THR (UART_BASE + 0)            // the device
+#define UART_RBR (UART_BASE + 0)
+#define UART_LSR (UART_BASE + 5)
+
+void serial_putc(char c) {
+    while( (inb(UART_LSR) & 0x20)== 0);     // Wait until FIFO can hold more chars
+    outb(UART_THR, c);                      // Write character to FIFO
+}
+
+char serial_getc() {
+    while( (inb(UART_LSR) & 0x01) == 0);    // Wait until there is a char to read
+    return inb(UART_RBR);                   // Read from the receive FIFO
+}