Task and BMP Load question

(This message was transferred over from our old forum)
Posted December 24, 2015
By Ken Sec
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1.When the more task read or write global variable have question, the uez have porting vTaskSuspendAll() and xTaskResumeAll() ?

2.The BMPLoadScreen() is so slow of load BMP file, have any way can load fast it ?
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(Follow up post, Bill Fleming)

Ken,

1. uEZ has those task functions implemented in the uEZ API.
See uEZ\\Source\\RTOS\\uEZRTOS_FreeRTOS.c functions UEZTaskSchedulerSuspend and UEZTaskSchedulerResume.
Using a semaphore would be a better approach to accessing global variables from multiple tasks.

2. emWin has bitmap reading routines that are more optimized than the ones in uEZ. They also support compression for faster reading from external memory.
See here for more information. https://www.segger.com/emwin-displaying-bitmap-files.html
Note also that all LPC1788 uEZGUIs can use the high-speed 4-bit mode interface if you want to load a bunch of images from an SD card. By purchasing the inexpensive uEZGUI-EXP-BRKOUT board you can evaluate SD 4-bit mode on the uEZGUI-1788-56VI, uEZGUI-1788-70WVT, and uEZGUI-1788-43WQR. https://www.teamfdi.com/product-details/uezgui-exp-brkout/

Bill
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(Follow up post, Ken Sec)

Hi Bill:
I have buy uEZGUI-SD 1788-43WQR ,thanks your response.

I have new question , when I using UEZTaskDelete() ,the instantly task can be deleted , but the task resume work after some time.

How to complete delete task ?
[hr]
(Follow up post, Bill Fleming)

Ken,

I just tested this in uEZ 2.07 with the below code.

// Handel of uEZ Task
T_uezTask heartBeatTask;
// Create the task
UEZTaskCreate(Heartbeat, “Heart”, 64, (void *)0, UEZ_PRIORITY_NORMAL, &heartBeatTask);
//Delete the task
UEZTaskDelete(heartBeatTask);

In this example, I waited until after the uEZ menu loaded, then deleted the task. Then the LED heartbeat stopped blinking.

Deleting tasks in uEZ is not recommnded however since you might encounter memory leaks. It is recommended to use a blocking semaphore from another task if you want to just pause a specific task.

Bill