ColdFire/68K Microcontrollers and ProcessorsのトピックMCF5234: cannot initialize internal SRAM

MCF5234: cannot initialize internal SRAM

sirlenzelot — Thu, 29 Oct 2020 09:15:37 GMT

Hello everybody,

I have problems initializing the internal SRAM.

I rtfm and followed the steps described in Chapter 6.2.3 SRAM Initialization Code.

When I connect to my target via the BDI2000-interface by Abatron I have immediate access to SRAM as it is configured via the interface. They don't do anything different than me: write 0x20000001 to RAMBAR-register. But if I initialize the SRAM in my code, writing to RAMBAR has no effect.

This is what I do:

Code:

    INT_SRAM_BASE       EQU     $20000000      ; Base add used for internal SRAM    INT_SRAM_SIZE       EQU     $00010000      ; MCF5235 has 64K internal SRAM    INT_SRAM_VALID      EQU     $20000001      ; Bit to make internal SRAM                                               ; valid/enabled.    MOVE.W              #LOCKOUT,SR            ; Lock-out interrupts    MOVE.L              #INT_SRAM_VALID,D0    MOVEC.L             D0,RAMBAR0; zero SRAM    lea.l  INT_SRAM_BASE,A0    move.l  #INT_SRAM_SIZE,D0SRAM_INIT_LOOP:    clr.b  (A0)+    subq.l  #1,D0    bne.b  SRAM_INIT_LOOP; Init VBR    MOVE.L              #VECTOR_BASE,A0    MOVEC               A0,VBR; Init IPSBAR    MOVE.L              #IPSBAR,A0    MOVE.L              #IPSBAR_VALUE,(A0)

Can someone give me a hint on that, please?

Thanks in advance

Dirk

Re: MCF5234: cannot initialize internal SRAM

Arev — Thu, 29 Oct 2020 09:15:39 GMT

Hello,

I use the following Init code, with RAMBAR1 instead of RAMBAR0

Code:

DEFAULT_IPSBAR  .equ    0x40000000REG_VALID       .equ    0x00000001RAM_DATACODE    .equ    0x00000020_BSP_Asm_BootCode:        move.w  #0x2700,sr        // IPSBAR 'Internal Peripheral System Base Address Register'

        move.l  #(___IPSBAR + REG_VALID),d0        move.l  d0,DEFAULT_IPSBAR        // RAMBAR Register 'SRAM Base Address Register' (RAMBAR1 = CPU+0x0C05)        move.l  #(___SRAM + RAM_DATACODE + REG_VALID),d0        movec   d0,RAMBAR1        // Temporary 'Stack Pointer' Init in SRAM (SDRAM not Initialized)        move.l  #(___SP_INIT_SRAM),sp        // Coldfire MCF523x Init (PLL & peripherals)        jsr     _BSP_ColdFire_InitialiserCPU        // 'Stack Pointer'        move.l  #(___SP_INIT),sp        // FreeScale 'C_4I_CF_RUNTIME.A' (E68k_Startup.c)        jmp     __start        .end

I Hope this helps..

Bye

<< Freescale MCF5234/35 with CodeWarrior 6.2 >>

Re: MCF5234: cannot initialize internal SRAM

sirlenzelot — Thu, 26 Jun 2008 16:47:49 GMT

Hi Arev,

we solved the problem.

Our compiler was setup for using 5200. RAMBAR0 at CPU@0xC04 is used.

As we changed to 5234, everything is okay and RAMBAR1 at CPU@0xC05 is used.

Thanks

Dirk

Message Edited by sir lenzelot on 2008-06-26 11:48 AM