simple mutex demo on lpc4337

Dependencies:   ST7567

Fork of lpc4337_mbed_os_semaphore_demo by Felipe Neves

Files at this revision

API Documentation at this revision

Comitter:
uLipe
Date:
Mon Oct 03 23:08:57 2016 +0000
Parent:
0:d767141a0a9c
Commit message:
first working commit

Changed in this revision

main.cpp Show annotated file Show diff for this revision Revisions of this file
--- a/main.cpp	Wed Sep 28 16:28:49 2016 +0000
+++ b/main.cpp	Mon Oct 03 23:08:57 2016 +0000
@@ -11,6 +11,9 @@
 #define FONT_HEIGHT         10
 #define FONT_WIDTH          5
 
+#define RT_TASK             0x8001
+#define HP_TASK             0x8002
+
 
 /* allocate statically stacks for the three threads */
 unsigned char rt_stk[1024];
@@ -23,40 +26,62 @@
 Thread low_prio_thread(osPriorityNormal, 1024, &lp_stk[0]);
 
 
-/* creates semaphores to explore the capabilites of synchronization */
-Semaphore rt_sema;
-Semaphore hp_sema;
-const char rt_message[] = {"rt_task() sema:\0"};
-const char hp_message[] = {"hp_task() sema:\0"};
-const char lp_message[] = {"np_task() exec:\0"};
+/* crates a mutex that will help us to controll a resource access */
+Mutex message_lock;
 
+/* console buffer which has shared access */
+char console_buffer[64] = {0};
 
 
 /* creates a instance of display */
 ST7567  disp(D11, D13, D12, D9, D10);
 
+/**
+ * @brief prints the current task which executes:
+ */
+static void log_thread(int t, int noof_exec) {
+    
+    /* try to take the mutex, or wait until becomes avalialble*/
+    
+    
+    disp.cls();
+    
+    disp.locate(0, FONT_HEIGHT * 1);
+    disp.printf("Thread status: ");
 
+    disp.locate(0, FONT_HEIGHT * 2);  
+    if(t ==  RT_TASK) {
+        message_lock.lock();
+        strcpy(&console_buffer[0], "-current thread: rt_task();\0" );    
+        message_lock.unlock();
+        disp.printf("%s", console_buffer);
+    } else {
+        message_lock.lock();
+        strcpy(&console_buffer[0], "-current thread: hp_task();\0" );    
+        message_lock.unlock();
+        disp.printf("%s", console_buffer);
+    }     
+
+    disp.locate(0, FONT_HEIGHT * 3);
+    disp.printf("-noof executions: %d ;", noof_exec);  
+    disp.locate(0, FONT_HEIGHT * 4);
+    disp.printf("-mutex status: taken .");
+    
+
+}
 
 
 /**
  * @brief real time prio task function 
  */
-static void rt_task(void) {
-
-    disp.locate(0, FONT_HEIGHT * 2);            
-    disp.printf(rt_message);
-    rt_sema.wait();               
+static void rt_task(void) {    
+    int execs = 0;
     
     
     for(;;) {
-            
-         /* dsiplay the semaphore status */
-         disp.locate((sizeof(lp_message) * FONT_WIDTH), FONT_HEIGHT * 4);
-         disp.printf("WAIT!");
-
-         disp.locate((sizeof(rt_message) * FONT_WIDTH), FONT_HEIGHT * 2);
-         disp.printf("TOOK!");
-         rt_sema.wait();           
+        execs++;
+        log_thread(RT_TASK, execs);
+        Thread::wait(2000);
     }
     
 }
@@ -65,20 +90,13 @@
  * @brief high prio task function 
  */
 static void hp_task(void){    
-    disp.locate(0, FONT_HEIGHT * 3);
-    disp.printf(hp_message);
-    hp_sema.wait();           
 
+    int execs = 0;
     
     for(;;) {
-
-         /* dsiplay the semaphore status */
-         disp.locate((sizeof(lp_message) * FONT_WIDTH), FONT_HEIGHT * 4);
-         disp.printf("WAIT!");
-
-         disp.locate((sizeof(hp_message) * FONT_WIDTH), FONT_HEIGHT * 3);
-         disp.printf("TOOK!");  
-         hp_sema.wait();       
+        execs++;
+        log_thread(HP_TASK, execs);
+        Thread::wait(2000);
     }
 }
 
@@ -86,31 +104,10 @@
  * @brief normal prio task function 
  */
 static void np_task(void) {
-        
-    disp.locate(0, FONT_HEIGHT * 4);
-    disp.printf(lp_message);
-
-    disp.locate((sizeof(lp_message) * FONT_WIDTH), FONT_HEIGHT * 4);
-    disp.printf("RUNN!");
-    disp.locate((sizeof(rt_message) * FONT_WIDTH), FONT_HEIGHT * 2);
-    disp.printf("WAIT!");
-    disp.locate((sizeof(hp_message) * FONT_WIDTH), FONT_HEIGHT * 3);
-    disp.printf("WAIT!");
-
+    
+    Thread::wait(0);        
     
     for(;;) {
-         rt_sema.release();        
-         disp.locate((sizeof(rt_message) * FONT_WIDTH), FONT_HEIGHT * 2);
-         disp.printf("WAIT!");
-         disp.locate((sizeof(lp_message) * FONT_WIDTH), FONT_HEIGHT * 4);
-         disp.printf("RUNN!");
-
-
-         hp_sema.release();          
-         disp.locate((sizeof(hp_message) * FONT_WIDTH), FONT_HEIGHT * 3);
-         disp.printf("WAIT!");
-         disp.locate((sizeof(lp_message) * FONT_WIDTH), FONT_HEIGHT * 4);
-         disp.printf("RUNN!");
          
     }
 }