μC/OS-II experiment: Experiment 5 Memory Management

Tutorial Description :... Involved μC/OS-II system function :... Experiment code: App. c

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Static void showmeminfo (void) { OS _mem_data mem_data; Osmemquery (pmem, & mem_data ); Printf ("begining address of memory: \ t % x \ r \ n", (INT) (mem_data.osaddr )); Printf ("block size in the memory area: \ t % d \ r \ n", (INT) (mem_data.osblksize )); Printf ("Free blocks in the memory area: \ t % d \ r \ n", (INT) (mem_data.osnfree )); Printf ("used blocks in the memory area: \ t % d \ r \ n", (INT) mem_data.osnused ); Printf ("\ r \ n "); Ostimedlyhmsm (0, 0, 2, 0 ); } Static void getmem (int8u I) { Int8u err; // Apply for memory space Pmemmsg [I] = osmemget (pmem, & ERR ); If (pmemmsg [I]! = (Void *) null & err = OS _no_err) { Printf ("got memory _ % d. \ r \ n", I); // The memory block has been allocated Showmeminfo (); } Else Printf ("not got memory _ % d. \ r \ n", I ); } Static void putmem (void * pmemmsg, int8u I) { Int8u err; // Release memory space Err = osmemput (pmem, pmemmsg ); If (ERR = OS _no_err) { Printf ("released memory _ % d. \ r \ n", I);/* release the memory block */ Showmeminfo (); } Else Printf ("not exist memory _ % d. \ r \ n", I ); } Void taskmem1 (void * pdata) { Int8u I; I = 0; While (1) { Getmem (I ++ % msgsize ); Ostimedlyhmsm (0, 0, 2, 0 ); } } Void taskmem2 (void * pdata) { Int8u I; I = 0; While (1) { Putmem (pmemmsg [I ++ % msgsize], I ++ % msgsize ); Ostimedlyhmsm (0, 0, 2, 0 ); } }

App. h

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# Define msgsize 3 Global OS _mem * pmem; // set the returned value storage for the osmemcreate Function Global void * pmemmsg [3]; // store the returned values for the osmemget Function Global int8u membuf [2] [128]; // initialize the memory allocated space

App_cfg.h

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# Define mem1_stk_size 64 # Define mem2_stk_size 64 # Define mem1_task_prio 20 # Define mem2_task_prio 21 Global OS _stk task_mem1_stk [mem1_stk_size]; Global OS _stk task_mem2_stk [mem2_stk_size]; Void taskmem1 (void * pdata ); Void taskmem2 (void * pdata );

Main. C: taskstart

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/* Experiment 5 memory management */ Pmem = osmemcreate (membuf, 2,128, & ERR ); Ostaskcreate (taskmem1, 0, (OS _stk *) & task_mem1_stk [mem1_stk_size-1], mem1_task_prio ); Ostaskcreate (taskmem2, 0, (OS _stk *) & task_mem2_stk [mem2_stk_size-1], mem2_task_prio );

Experiment results: taskmem1 applied for memory space and taskmem2 released the memory space. Note: If the memory is successfully obtained, the condition is (pmemmsg [I]! = (Void *) null & err = OS _no_err ). Reference materials and supporting code: uCOS-II experiment guide ucos_demo Note: It is correct to refer to this document, but there is a reason why I put it at the end, because there are problems with the concept or code of several experiments (almost every ⊙ ﹏ ⊙ B Khan, I have pointed out earlier. If you are not clear about it, let's make a comparison.