R01US0068EJ0100 Datasheet, PDF (26/56 Pages) Renesas Technology Corp – EEPROM Emulation Library

RL78 Family
EEPROM Emulation Library Pack02
Chapter 4 Using EEPROM Emulation
Table 4-2 Points for Caution (1/2)
No
Caution Points
12 After the FDL_Close and EEL_Close functions have been executed, the requested command and ongoing
command stop and cannot be resumed. Before calling the FDL_Close and EEL_Close functions, finish all
ongoing commands.
13 Before using the EEPROM emulation library, always close the FSL. Also, do not run the FSL while the
EEPROM emulation library is being used. When using the FSL, be sure to execute all of the processing up
to and including the EEL_Close function and FDL_Close function to finish EEPROM emulation.
When using EEPROM emulation after executing FSL processing, it is necessary to start processing from
the initializing function (the FDL_Init function).
14 Before starting the EEPROM emulation, be sure to start up the high-speed on-chip oscillator first. The
high-speed on-chip oscillator must also be activated when using the external clock.
15 In address above 0xFFE20 (0xFE20), do not place data buffer (argument) or stack which is used by
EEL functions and FDL functions.
16 When using data transfer controller (DTC) during EEPROM emulation, do not place RAM area used by
DTC in self-RAM and in address above 0xFFE20 (0xFE20).
17 Until EEPROM emulation is finished, do not corrupt RAM area (including self-RAM) used by EEPROM
emulation.
18 No checksum is added to user data. If a checksum is needed, add it to user data and check through the
user program.
19 When the FDL descriptor or EEL descriptor is changed, the EEPROM emulation can no longer be
executed. In that case, the EEL pool must be formatted by the EEL_CMD_FORMAT command in addition
to initialization of FDL and EEL. When adding data, however, the EEPROM emulation can be continuously
executed.
20 Do not operate the Data Flash Control Register (DFLCTL) during the execution of the EEL.
21 To use the data flash memory for EEPROM emulation, it is necessary to execute the
EEL_CMD_FORMAT command upon first starting up to initialize the data flash memory and make it
usable as EEPROM emulation blocks.
22 It is recommended that at least three blocks be provided in the data flash memory to use the EEL.
23 Do not destroy EEL blocks by the user program that uses other EELs or FDLs.
24 The EEL does not support multitask execution. When executing an EEL function on the OS, do not
execute in from two or more tasks.
25 About an operation frequency of RL78 microcontrollers and an operation frequency value set by the
initializing function (FDL_Init), be aware of the following points:
-When using a frequency lower than 4 MHz as an operation frequency of RL78 microcontrollers, only 1
MHz, 2 MHz and 3 MHz can be used (frequencies other than integer values like a 1.5 MHz cannot be
used). Also, set an integer value 1, 2, or 3 to the operation frequency value set by the initializingfunction.
- When using a frequency of 4 MHz or higher ^Note1 as an operation frequency of RL78 microcontrollers, a
certain frequency can be used as an operation frequency of RL78 microcontrollers.
- This operation frequency is not the frequency of the high-speed on-chip oscillator.
Note 1: For a maximum frequency, see the target RL78 microcontroller user’s manual.
R01US0068EJ0100 Rev.1.00
Mar. 28, 2014
Page 26 of 53