1 files changed, 20 insertions, 2 deletions
diff --git a/interrupts.c b/interrupts.c
index 7932d23..f47bc1d 100644
--- a/interrupts.c
+++ b/interrupts.c
@@ -1,4 +1,5 @@
 #include "uart.h"
+#include "svc_interface.h"
 
 void setup(void);
 
@@ -24,9 +25,26 @@ void undefined_instruction_vector(void)
     }
 }
 
-void supervisor_call_handler(void)
+uint32_t supervisor_call_handler(enum svc_type request, uint32_t arg1,
+				 uint32_t arg2, uint32_t arg3)
 {
-  uart_puts("something svc happened\n\r");
+  (void) arg2; (void) arg3; // unused for now
+  
+  switch(request) {
+  case UART_PUTCHAR:
+    uart_putc(arg1);
+    break;
+  case UART_GETCHAR:
+    return uart_getc();
+  case UART_WRITE:
+    uart_puts("UART_WRITE not implemented!!!!!\n\r");
+    break;
+  default:
+    // perhaps we should kill the process now?
+    uart_puts("unknown supervisor call type!!!!!\n\r");
+  }
+
+  return 0; // a dummy value
 }
 
 void abort_handler(void)