diff --git a/testcode/lib/mul-test.c b/testcode/lib/mul-test.c
new file mode 100644
index 000000000..56fd77681
--- /dev/null
+++ b/testcode/lib/mul-test.c
@@ -0,0 +1,95 @@
+#include <time.h>
+#include <conio.h>
+#include <ctype.h>
+
+
+/* Number of elements in the progress bar. Use a power of 2 to avoid the
+ * multiplication (which is about to be tested).
+ */
+#define BAR_ELEMENTS    32U
+
+/* Screen coordinates for the progress meter */
+static unsigned char Width, Height;
+static unsigned char X, Y;
+
+static void ProgressMeter (unsigned Val)
+/* Print the progress bar */
+{
+    cclearxy (X, Y, Width);
+    gotoxy (X, Y);
+    cprintf ("% 6lu/65536", (unsigned long) Val);
+}
+
+
+
+int main(void)
+{
+    char C;
+
+    /* Clock variable */
+    clock_t Ticks;
+    unsigned Sec;
+    unsigned Milli;
+
+    /* Actual test variables */
+    register unsigned lhs = 0;
+    register unsigned rhs = 0;
+    register unsigned res;
+
+    /* Clear the screen and output an informational message */
+    clrscr ();
+    screensize (&Width, &Height);
+    cprintf ("This program does an exhaustive test of\r\n"
+             "the multiplication routine. It runs\r\n"
+             "several days, so please wait very\r\n"
+             "patiently (or speedup your emulator)\r\n"
+             "\r\n"
+             "Progress:\r\n");
+
+    /* Remember the current position for the progress bar */
+    X = wherex ();
+    Y = wherey ();
+
+
+    /* Read the clock */
+    Ticks = clock();
+
+
+    do {
+
+        /* Update the progress bar */
+        ProgressMeter (lhs);
+
+        /* Do one row of tests */
+        res = 0;
+        do {
+            if (lhs * rhs != res) {
+                gotoxy (X, Y+1);
+                cprintf ("Error on %u * %u: %u != %u\r\n", lhs, rhs, lhs * rhs, res);
+                cprintf ("Press a key ..., 'Q' to quit");
+                C = toupper (cgetc ());
+                cclearxy (X, Y+1, Width);
+                cclearxy (X, Y+2, Width);
+                if (C == 'Q') {
+                    goto Done;
+                }
+            }
+            res += lhs;
+        } while (++rhs != 0);
+
+    } while (++lhs != 0);
+
+Done:
+    /* Calculate the time used */
+    Ticks = clock() - Ticks;
+    Sec = (unsigned) (Ticks / CLOCKS_PER_SEC);
+    Milli = ((Ticks % CLOCKS_PER_SEC) * 1000) / CLOCKS_PER_SEC;
+
+    /* Print the time used */
+    gotoxy (X, Y+1);
+    cprintf ("Time used: %u.%03u seconds\n", Sec, Milli);
+
+    return 0;
+}
+
+