Thanks to Zoltan Hudak publish the way to use STM32F103c8t6 on mbed. Now, this example can let you use it with a encoder.

Dependencies:   QEI mbed-STM32F103C8T6 mbed

Fork of STM32F103C8T6_Hello by Zoltan Hudak

Revision:
0:ab218237069e
Child:
1:1dd12d8c840d
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp	Sat Jul 02 07:22:32 2016 +0000
@@ -0,0 +1,12 @@
+#include "mbed.h"
+
+DigitalOut myled(LED1);
+
+int main() {
+    while(1) {
+        myled = 1; // LED is ON
+        wait(0.2); // 200 ms
+        myled = 0; // LED is OFF
+        wait(1.0); // 1 sec
+    }
+}