Working UART implementation

src/uart.js

@@ -2,31 +2,219 @@
  * No full implementation, just dumping serial output
  * to console
  *
+ */
+
+/** @const */
+var DLAB = 0x80;
+
+/** 
  * @constructor 
  */
-function UART(dev, adapter)
+function UART(dev, port, adapter)
 {
     var io = dev.io,
-        line = "";
+        pic = dev.pic,
 
-    io.register_write(0x3F8, function(out_byte) 
+        line = "",
+        baud_rate = 0,
+
+        line_control = 0,
+        line_status = 0,
+
+        fifo_control = 0,
+        interrupt_enable = 0,
+
+        modem_control = 0,
+        modem_status = 0,
+
+        scratch_register = 0,
+
+        irq = 0,
+
+        input = new ByteQueue(4096);
+
+    if(port === 0x3E8 || port === 0x3F8)
     {
-        if(out_byte === 0x0A)
-        {
-            adapter.send_line(line);
-            dbg_log(line, LOG_SERIAL);
+        irq = 4;
+    }
+    else if(port === 0x3E8 || port === 0x3E8)
+    {
+        irq = 3;
+    }
+    else
+    {
+        dbg_log("Invalid port: " + h(port), LOG_SERIAL);
+        return;
+    }
 
-            line = "";
+    function data_received(data)
+    {
+        input.push(data);
+
+        if(interrupt_enable & 1)
+        {
+            push_irq();
+        }
+    }
+    adapter.init(data_received);
+
+    function push_irq()
+    {
+        pic.push_irq(irq);
+    }
+
+    io.register_write(port, function(out_byte) 
+    {
+        if(line_control & DLAB)
+        {
+            baud_rate = baud_rate & ~0xFF | out_byte;
+            return;
+        }
+
+        //dbg_log("data: " + h(out_byte), LOG_SERIAL);
+
+        if(out_byte === 0xFF)
+        {
+            return;
+        }
+
+        if(!adapter)
+        {
+            return;
+        }
+
+        if(adapter.put_line)
+        {
+            if(out_byte === 0x0A)
+            {
+                adapter.put_line(line);
+                line = "";
+            }
+            else
+            {
+                line += String.fromCharCode(out_byte);
+            }
         }
         else
         {
-            line += String.fromCharCode(out_byte);
+            adapter.put_str(String.fromCharCode(out_byte));
         }
     });
 
-    io.register_read(0x3FD, function(out_byte) 
+    io.register_write(port | 1, function(out_byte)
     {
-        // TODO
-        return 0xFF;
+        if(line_control & DLAB)
+        {
+            baud_rate = baud_rate & 0xFF | out_byte << 8;
+            dbg_log("baud rate: " + h(baud_rate), LOG_SERIAL);
+        }
+        else
+        {
+            interrupt_enable = out_byte;
+            dbg_log("interrupt enable: " + h(out_byte), LOG_SERIAL);
+        }
+    });
+
+    io.register_read(port, function()
+    {
+        if(line_control & DLAB)
+        {
+            return baud_rate & 0xFF;
+        }
+        else
+        {
+            var data = input.shift();
+
+            if(data === -1)
+            {
+                dbg_log("Input empty", LOG_SERIAL);
+            }
+            else
+            {
+                dbg_log("Input: " + h(data), LOG_SERIAL);
+            }
+
+            return data;
+        }
+    });
+
+    io.register_read(port | 1, function()
+    {
+        if(line_control & DLAB)
+        {
+            return baud_rate >> 8;
+        }
+        else
+        {
+            return interrupt_enable;
+        }
+    });
+
+    io.register_read(port | 2, function()
+    {
+        return fifo_control;
+    });
+    io.register_write(port | 2, function(out_byte)
+    {
+        dbg_log("fifo control: " + h(out_byte), LOG_SERIAL);
+        fifo_control = out_byte;
+    });
+
+    io.register_read(port | 3, function()
+    {
+        return line_control;
+    });
+    io.register_write(port | 3, function(out_byte)
+    {
+        dbg_log("line control: " + h(out_byte), LOG_SERIAL);
+        line_control = out_byte;
+    });
+
+
+    io.register_read(port | 4, function()
+    {
+        return modem_control;
+    });
+    io.register_write(port | 4, function(out_byte)
+    {
+        dbg_log("modem control: " + h(out_byte), LOG_SERIAL);
+        modem_control = out_byte;
+    });
+
+    io.register_read(port | 5, function()
+    {
+        var line_status = 0;
+
+        if(input.length)
+        {
+            line_status |= 1;
+        }
+
+        line_status |= 0x20;
+
+        //dbg_log("read line status: " + h(line_status), LOG_SERIAL);
+        return line_status;
+    });
+    io.register_write(port | 5, function(out_byte)
+    {
+    });
+
+    io.register_read(port | 6, function()
+    {
+        //dbg_log("read modem status: " + h(modem_status), LOG_SERIAL);
+        return modem_status;
+    });
+    io.register_write(port | 6, function(out_byte)
+    {
+        modem_status = out_byte;
+    });
+
+    io.register_read(port | 7, function()
+    {
+        return scratch_register;
+    });
+    io.register_write(port | 7, function(out_byte)
+    {
+        scratch_register = out_byte;
     });
 }