Add support for sending debug messages to a serial port.

Enable by turning on CONFIG_DEBUG_SERIAL option.

1 files changed, 8 insertions, 1 deletions

diff --git a/src/output.c b/src/output.c
index fc77c214..b2f28e9f 100644
--- a/src/output.c
+++ b/src/output.c
@@ -24,8 +24,15 @@ screenc(u8 c)
 static void
 putc(u16 action, char c)
 {
-    outb(c, PORT_BIOS_DEBUG);
+    if (CONFIG_DEBUG_SERIAL)
+        // Send character to serial port.
+        debug_serial(c);
+    else
+        // Send character to debug port.
+        outb(c, PORT_BIOS_DEBUG);
+
     if (action) {
+        // Send character to video screen.
         if (c == '\n')
             screenc('\r');
         screenc(c);