* Implemented serial IO

* Fixed some typos
* Updated Makefile
* Deleted object files

Author: Arun007coder

.gitignore

@@ -1,4 +1,6 @@
 *.elf
 *.iso
 .vscode
-.vscode/*
+.vscode/*
+**/*.o
+src/kernel/kernel.o

Makefile

@@ -32,6 +32,7 @@ ISOFILE=$(PROJECT).iso
 OBJECTS= 	$(SRCDIR)/boot/boot.o \
 			$(SRCDIR)/drivers/io/ports.o \
 			$(SRCDIR)/common/system.o \
+			$(SRCDIR)/drivers/io/serial.o \
 			$(SRCDIR)/kernel/kernel.o
 
 all: kernel iso

docs/README.md

@@ -2,7 +2,7 @@
 
 A new rewrite of SectorOS_RE2.
 
-The kernel is currently v0.23.03.1ALP
+The kernel is currently v0.23.03.1ALPR
 
 ## Build
 

docs/changelog.txt

@@ -5,4 +5,11 @@
 * Added link.ld
 * Added system.h
 * Added system.c
-* Implemented port IO
+* Implemented reboot
+* Implemented port IO
+
+26-03-2023: 08:48 PM IST v0.23.03.1ALPR
+* Implemented serial IO
+* Fixed some typos
+* Updated Makefile
+* Deleted object files

src/boot/boot.o

@@ -0,0 +1,75 @@
+#include "serial.h"
+
+serialio_t serial;
+
+#define PORT serial.port
+
+int init_serial(uint16_t port, int skip_test)
+{
+    serial.port = port;
+    serial.type = SERIALIO_COMMUNICATION;
+    serial.skip_test = skip_test;
+    
+    
+    outb(serial.port + 1, 0x00);
+    outb(serial.port + 3, 0x80);
+    outb(serial.port + 0, 0x03);
+    outb(serial.port + 1, 0x00);
+    outb(serial.port + 3, 0x03);
+    outb(serial.port + 2, 0xC7);
+    outb(serial.port + 4, 0x0B);
+
+    if(skip_test != 1)
+    {
+        outb(serial.port + 4, 0x1E);
+        outb(serial.port + 0, 0xAE);
+        if(inb(serial.port + 0) != 0xAE)
+        {
+            return;
+        }
+    }
+
+    outb(serial.port + 4, 0x0F);
+}
+
+int serial_received()
+{
+    return inb(serial.port + 5) & 1;
+}
+
+char read_serial()
+{
+    while(serial_received() == 0)
+
+    return inb(serial.port);
+}
+
+int is_transmit_empty()
+{
+    return inb(serial.port + 5) & 0x20;
+}
+
+void write_serial(char val)
+{
+    while(is_transmit_empty() == 0);
+    outb(serial.port, val);
+}
+
+void serial_putc(char c)
+{
+    if(c == '\n')
+    {
+        write_serial('\r\n');
+        return;
+    }
+    write_serial(c);
+}
+
+void serial_puts(char* str)
+{
+    while(*str != 0)
+    {
+        serial_putc(*str);
+        str++;
+    }
+}

src/common/system.o

@@ -0,0 +1,27 @@
+#ifndef __SERIAL_H__
+#define __SERIAL_H__
+
+#include "system.h"
+#include "ports.h"
+
+#define COM1 0x3F8
+#define COM2 0x2F8
+#define COM3 0x3E8
+#define COM4 0x2E8
+
+#define SERIALIO_COMMUNICATION 0
+
+typedef struct serialio
+{
+    uint32_t type;
+    uint16_t port;
+    int skip_test;
+}serialio_t;
+
+int init_serial(uint16_t port, int skip_test);
+void serial_putc(char c);
+void serial_puts(char* str);
+
+char read_serial();
+
+#endif /*__SERIAL_H__*/

src/drivers/io/ports.o

@@ -1,11 +1,18 @@
 #include "system.h"
 #include "multiboot.h"
+#include "serial.h"
 
 void kernelmain(const multiboot_info_t* info, uint32_t multiboot_magic)
 {
+    init_serial(COM1, 0);
     if(multiboot_magic != 0x2BADB002)
     {
+        serial_puts("multiboot bootloader magic is invalid\n");
         return;
     }
+    serial_puts("multiboot bootloader magic is valid...\n");
+    serial_puts("Kernel version is:");
+    serial_puts(KERNEL_VERSION);
+    serial_putc('\n');
     reboot();
 }