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Renesas Electronics America - Knowledgebase

Why the program doesn't operate correctly in RX family MCU?

Latest Updated:09/05/2013


I am debugging an RX family MCU using the E1 or E20 emulator.
I have downloaded and executed a program, but the program does not operate correctly.


The endian setting may be incorrect.
Confirm that the endian setting in the build tool matches the endian setting in the microcontroller.

  1. Setting the endian in the build tool
    • When CubeSuite+ is used:
      (1) Select the [Common Options] tab on the Property panel of the build tool.
      (2) Confirm the setting from [CPU] -> [Endian type for data].
      For details, refer to CubeSuite+ Integrated Development Environment User's Manual: RX Build from here.

    • When High-performance Embedded Workshop is used
      (1) From the High-performance Embedded Workshop menu [Build], select [RX Standard Toolchain...] to open the RX Standard Toolchain dialog box.
      (2) Select the [CPU] tab and confirm the setting in the [Endian] pull-down menu.

  2. Setting the endian in the microcontroller
    The setting method differs for each microcontroller group.
    • For the RX610, RX621, RX62N, RX62T, RX62G group:
      The endian is determined by the MDE pin level.

    • For other groups:
      The endian is set by the endian select register.
      Since the endian select register is located in flash memory, the setting has to be written to the respective address in the user program. Depending on the startup routine, the endian select register is automatically set in accordance with the endian setting of the build tool (see vecttbl.c).

      For details, refer to the hardware manual of the microcontroller in use.
Suitable Products
CS+ (formerly CubeSuite+)
High-performance Embedded Workshop
C/C++ Compiler Package for RX Family
E1 [R0E000010KCE00]
E20 [R0E000200KCT00]