MQX BSP for MCF52255

[trusc]

MQX supports the M52259DEMO board, but I'm using the MCF52255 in a new project. Does anyone out there perhaps use this device? If so, I would appreciate it if you could give me and idea of how much effort is involved in modifying the existing BSP to support the MCF52255.

Thanks.

[trailman · Accepted solution]

Hi,

The BSP for M52259EVB should work as is on your MCF52255 board, however as MCF52255 has no flexbus, you must comment-out the following code in mqx/source/bsp/m52259evb/bsp_init.c :

#if 0

    /* Enable Mini FlexBUS signals (used by external MRAM and CPLD) */
    reg_ptr->GPIO.PASPAR = 0x20;   /* enable CS1 operation for CPLD */
    reg_ptr->GPIO.PTEPAR = 0xff;
    reg_ptr->GPIO.PTFPAR = 0xff;
    reg_ptr->GPIO.PTGPAR = 0xff;   /* enable CS0 operation for MRAM */
    reg_ptr->GPIO.PTHPAR = 0x5555;
    
    _bsp_flexbus_mram_setup((uint_32)BSP_EXTERNAL_MRAM_BASE);    
#endif

If you don't do that the BSP will fail to start hanging here.

Also check that the 80Mhz frequency used on MCF52259EVB is allowed on your CPU.

I worked on an MCF52254 and had to reduce the frequency below 66Mhz by doing changes for PLL settings in the same file.

[trusc]

Thanks for the help. I'll try this now that I'm getting back into the project after the holidays. Sorry for the belated reply.