4 files changed, 85 insertions, 0 deletions
diff --git a/frontends/calculator/CEdev/examples/stopwatch/makefile b/frontends/calculator/CEdev/examples/stopwatch/makefile
new file mode 100644
index 0000000..1f1b36b
--- /dev/null
+++ b/frontends/calculator/CEdev/examples/stopwatch/makefile
@@ -0,0 +1,15 @@
+# ----------------------------
+# Set NAME to the program name
+# Set ICON to the png icon file name
+# Set DESCRIPTION to display within a compatible shell
+# Set COMPRESSED to "YES" to create a compressed program
+# ----------------------------
+
+NAME        ?= DEMO
+COMPRESSED  ?= NO
+ICON        ?= iconc.png
+DESCRIPTION ?= "C SDK Demo"
+
+# ----------------------------
+
+include $(CEDEV)/include/.makefile
diff --git a/frontends/calculator/CEdev/examples/stopwatch/readme.md b/frontends/calculator/CEdev/examples/stopwatch/readme.md
new file mode 100644
index 0000000..a10bdb9
--- /dev/null
+++ b/frontends/calculator/CEdev/examples/stopwatch/readme.md
@@ -0,0 +1,10 @@
+### Stopwatch Demo
+
+This demo demonstrates using the hardware timers to make a simple stopwatch
+displaying millisecond precision.
+
+![Screenshot](screenshot.png)
+
+---
+
+This demo is a part of the C SDK Toolchain for use on the CE.
diff --git a/frontends/calculator/CEdev/examples/stopwatch/screenshot.png b/frontends/calculator/CEdev/examples/stopwatch/screenshot.png
new file mode 100644
index 0000000..3642282
--- /dev/null
+++ b/frontends/calculator/CEdev/examples/stopwatch/screenshot.png
diff --git a/frontends/calculator/CEdev/examples/stopwatch/src/main.c b/frontends/calculator/CEdev/examples/stopwatch/src/main.c
new file mode 100644
index 0000000..3ec82b1
--- /dev/null
+++ b/frontends/calculator/CEdev/examples/stopwatch/src/main.c
@@ -0,0 +1,60 @@
+#include <stdbool.h>
+#include <stddef.h>
+#include <stdint.h>
+#include <tice.h>
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+/* Print a stopwatch value on the home screen */
+void print(float elapsed) {
+    /* Float format for printf may be unimplemented, so go through an OS real */
+    real_t elapsed_real;
+
+    /* Max stopwatch value is (2^32 - 1) / 32768 = 131072.00, */
+    /* so create a buffer with room for 9 characters plus a null terminator */
+    char str[10];
+
+    /* If the elapsed time is small enough that the OS would print it using */
+    /* scientific notation, force it down to zero before conversion */
+    elapsed_real = os_FloatToReal(elapsed <= 0.001f ? 0.0f : elapsed);
+
+    /* Convert the elapsed time real to a string */
+    os_RealToStr(str, &elapsed_real, 8, 1, 2);
+
+    /* Print the string */
+    os_SetCursorPos(0, 0);
+    os_PutStrFull(str);
+}
+
+/* Put all your code here */
+void main(void) {
+    /* Clear the homescreen */
+    os_ClrHome();
+
+    /* Display an initial time of zero */
+    print(0.0f);
+
+    /* Disable the timer */
+    timer_Control = TIMER1_DISABLE;
+
+    /* Reset the timer's counter */
+    timer_1_Counter = 0;
+
+    /* Wait for a key press */
+    while (!os_GetCSC());
+
+    /* Enable the timer while setting it to 32768 KHz and making it count up */
+    timer_Control = TIMER1_ENABLE | TIMER1_32K | TIMER1_UP;
+
+    /* Continue running until a key is pressed */
+    do {
+        /* Calculate and print the elapsed time */
+        float elapsed = (float)atomic_load_increasing_32(&timer_1_Counter) / 32768;
+        print(elapsed);
+    } while (!os_GetCSC());
+
+    /* Wait for a key press */
+    while (!os_GetCSC());
+}