i am using rl78g15 new 20 pin controller , in application need to store the varible in eeprom and fetch after power transition (last state of the varible),please support
thanks in advance.....
thank you for sharing details here will see how much i can help you
To store a variable in EEPROM on the RL78G15 microcontroller, you can use the built-in data flash memory, which can be programmed…
Define the variable you want to store in dataflash or EEPROM. For example, if you want to store an integer value, you can define it like this:int myVar = 1234;Declare the memory location where you want…
To store a variable in EEPROM on the RL78G15 microcontroller, you can use the built-in data flash memory, which can be programmed in-system. Here's a general overview of the steps you can follow:
Define a variable to be stored in EEPROM. Let's say this variable is called "myVar".
Declare a pointer to the EEPROM location where you want to store the variable. For example, if you want to store the variable at address 0x4000 in data flash memory, you can declare a pointer as follows:
cCopy codevolatile unsigned char *eeprom_ptr = (volatile unsigned char *) 0x4000;Write the variable to EEPROM using the pointer. You can use the built-in data flash programming functions to do this. Here's an example:scssCopy code* eeprom_ptr = myVar;FLASH.DFLRE = 0x0A; // set DFLRE bit to start programmingwhile(FLASH.DFLRE != 0); // wait for programming to completeNote that you need to set the DFLRE bit to start programming, and wait for the programming to complete before accessing the data flash memory again.
To read the variable from EEPROM after power transition, you can simply read it from the same EEPROM location using the pointer. Here's an example:makefileCopy codemyVar = * eeprom_ptr;Make sure to initialize the variable to a known value before reading from EEPROM, in case it has not been previously programmed.
I hope this helps! Let me know if you have any further questions.
Define the variable you want to store in dataflash or EEPROM. For example, if you want to store an integer value, you can define it like this:int myVar = 1234;Declare the memory location where you want to store the variable. For example, if you want to store the variable in EEPROM, you can declare a memory address like this:c#pragma location = 0xF000__root const int myVar_eeprom = myVar;Here, we've used the #pragma directive to specify the memory location 0xF000 for the myVar_eeprom variable. We've also used the __root attribute to ensure that the variable is not optimized out by the compiler.
If you want to store the variable in dataflash, you can use a similar approach but with a different memory location. For example:c#pragma location = 0x4000__root const int myVar_dataflash = myVar;Here, we've used the #pragma directive to specify the memory location 0x4000 for the myVar_dataflash variable.
Finally, you can write the variable to the appropriate memory location using a function like DataFlash_Write or EEPROM_Write. The specific function you use will depend on the type of memory you're using and how you've configured it. For example, if you're using EEPROM, you could write the variable like this:scssEEPROM_Write(&myVar_eeprom, &myVar, sizeof(myVar));Here, we're using the EEPROM_Write function to write the myVar variable to the myVar_eeprom memory location. We're also specifying the size of the variable using sizeof(myVar).
Thanks sir it is working for read perfectly .
Hello , I have a suggestion for you
To write a variable in RL78G15 in DataFlash/EEPROM that will be saved even after power off, you can follow these steps:
Declare the variable that you want to store in DataFlash/EEPROM as a "const" variable. For example:
const uint8_t my_variable = 0x55;
Include the "DataFlash.h" or "EEPROM.h" header file in your code, depending on which memory type you want to use. For example:
Initialize the DataFlash/EEPROM memory before writing or reading. For example:
DF_Init(); // Initialize DataFlash
Write the variable to DataFlash/EEPROM memory using the appropriate function. For example:
DF_WriteBlock(0x0000, (uint8_t *)&my_variable, sizeof(my_variable)); // Write to DataFlash
Here, "0x0000" is the address in DataFlash where you want to store the variable, and "&my_variable" is a pointer to the variable you want to write.
To read the variable from DataFlash/EEPROM memory, use the appropriate function. For example:
DF_ReadBlock(0x0000, &read_variable, sizeof(read_variable)); // Read from DataFlash
Here, "0x0000" is the address in DataFlash where the variable is stored, and "&read_variable" is a pointer to the variable where you want to store the read value.
Note that these steps may vary depending on the specific DataFlash/EEPROM memory module and the development environment you are using. Therefore, it is always best to consult the datasheet and reference manual of your specific RL78G15 microcontroller and DataFlash/EEPROM module to ensure that you are using the correct functions.
It isn't clear that it is understood that the RL78 data-flash is not EEPROM, which requires EEPROM emulation to implement wear-leveling to increase endurance / retention and provide resistance to resets for data loss. The G15 device requires the RFD/EES T01 software.
Only erased flash cells can be written (minimum write unit on G15 is 4-bytes), as such the block being written has to be pre-erased. Erase operations take a relatively long period of time, while a write operation is very fast in comparison. Using EEPROM emulation for a write incurs more overhead to use than a direct RFD write operation, unless there is a timing requirement such as trying to write data when power has been removed it would be recommended to use the EES.