Digole Digital Solution's Forum

bridge414 Total Posts: 6 Since: 2015-Aug-11 From: United States	Flash memory Posted at:2015-08-12 18:12:58
	I recently purchased a touch screen tft with 16M flash memory. I would like to know what flash memory addresses to avoid writing to. I don't want to write over the fonts or other things that are needed.

Service Total Posts: 414 Since: 2013-Dec-22 From: Canada	RE:Flash memory Posted at:2015-12-10 22:27:13
	The whole 16M flash can be used by yourself, the system fonts are stored in MCU flash, not in 16M flash memory.

bridge414

Total Posts:: 6
Since:: 2015-Aug-11
From:: United States

RE:Flash memory

Posted at:2015-12-14 18:26:05

Now I can't seem to get flashWrite to work. Any program that I have flashWrite in locks up when flashWrite is called. I also tried using the manual FLMWR command and the same thing is happening. The Flash memory test example also locks up. The MCU is also printing " Down Writing!" to the screen.

Erasing and reading from flash seem to be working.

My display is a 2.2 inch touchscreen with 16M flash and SD.

I'm using I2C on this device. Connected to Arduino Nano v3.

I have the SD working properly, so I can store data in it, but it would be nice to be able to store commands sets in the flash memory.

Service

Total Posts:: 414
Since:: 2013-Dec-22
From:: Canada

RE:Flash memory

Posted at:2015-12-14 21:35:33 Edited at:2015-12-14 21:41:57

1) Check "MEM_WP" jumper on the board, make sure it not shorted.

2) Run sample code: Touch_Flash_for_Checkbox_and_Radio_buttons

uncomment the following code:

//If your flash memory is blank, you need use the following 4 line of code to write command sets to flash

/*

flashErase(saddr,4096); //erase length of 4096 bytes for story command sets to drawing checkbox, and radio buttons

flashWrite(saddr,sizeof(checked), checked);

flashWrite(saddr+256, sizeof(uncheck), uncheck);

flashWrite(saddr+512, sizeof(radioChecked), radioChecked);

flashWrite(saddr+768, sizeof(radioUnchecked), radioUnchecked);

//*/

to

//If your flash memory is blank, you need use the following 4 line of code to write command sets to flash

//*

flashErase(saddr,4096); //erase length of 4096 bytes for story command sets to drawing checkbox, and radio buttons

flashWrite(saddr,sizeof(checked), checked);

flashWrite(saddr+256, sizeof(uncheck), uncheck);

flashWrite(saddr+512, sizeof(radioChecked), radioChecked);

flashWrite(saddr+768, sizeof(radioUnchecked), radioUnchecked);

//*/

and see if the code run like this:

https://www.youtube.com/watch?v=qKCvrKN4fbc

bridge414

Total Posts:: 6
Since:: 2015-Aug-11
From:: United States

RE:Flash memory

Posted at:2015-12-15 13:29:54

I checked the MEM_WP pads, and they were open.

I did the uncommenting and ran the radio and checkbox example, and it worked properly.

The flash memory test example is still not working. I noticed the flashWrite function there is only writing 2 bytes for length. The flashWrite function in the checkbox example is writing 3 bytes for length.

Also, Is it necessary to erase a block of flash memory before writing anything to it? If so, then that would be the problem I'm having with my code.

Service

Total Posts:: 414
Since:: 2013-Dec-22
From:: Canada

RE:Flash memory

Posted at:2015-12-16 20:45:41 Edited at:2015-12-16 21:05:28

We found the problem in sample code of "Digole_Flash_Mem_Test", this is old version when we developing the module, now, the erease commands are changed, please use the founction in sample of:Touch_Flash_for_Checkbox_and_Radio_buttons".

Yes, you only need earase 2 bytes before writing to it. use following commands:

flashErase(startAddress,2);

flashWrite(startAddress,2, pointerTo2bytes);

The module will use screen memory to store useful data in the block of flash where you just want earase partial of it, so, you will see massive dots at the bottom of screen. So, you can earase what ever the length of flash you want.

We just update the sample code for Arduino, please re-download it