1 files changed, 62 insertions, 0 deletions
diff --git a/libmaple/systick.h b/libmaple/systick.h
new file mode 100644
index 0000000..61789c4
--- /dev/null
+++ b/libmaple/systick.h
@@ -0,0 +1,62 @@
+/* *****************************************************************************
+ *  This program is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, either version 3 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ *  Created: 12/18/09 02:37:37
+ *  Copyright (c) 2009 Perry L. Hung. All rights reserved.
+ *
+ * ****************************************************************************/
+
+/**
+ *  @file systick.h
+ *
+ *  @brief Various system timer definitions
+ */
+
+#ifndef _SYSTICK_H_
+#define _SYSTICK_H_
+
+#include "libmaple.h"
+
+/* To the ARM technical manual... there's nearly nothing on the systick
+ * timer in the stm32 manual */
+
+#define SYSTICK_CSR       0xE000E010  // Control and status register
+#define SYSTICK_RELOAD    0xE000E014  // Reload value register
+#define SYSTICK_CNT       0xE000E018  // Current value register
+#define SYSTICK_CALIB     0xE000E01C  // Calibration value register
+
+#define SYSTICK_SRC_HCLK  BIT(2)    // Use core clock
+#define SYSTICK_TICKINT   BIT(1)    // Interrupt on systick countdown
+#define SYSTICK_ENABLE    BIT(0)    // Turn on the counter
+
+/* We use the systick timer to tick once
+ * every millisecond */
+#define MAPLE_RELOAD_VAL     72000
+
+#ifdef __cplusplus
+extern "C"{
+#endif
+
+void systick_init(void);
+
+static inline uint32_t systick_get_count(void) {
+    return (uint32_t)*(volatile uint32*)SYSTICK_CNT;
+}
+
+#ifdef __cplusplus
+} // extern "C"
+#endif
+
+#endif
+