S12 / MagniV MicrocontrollersのトピックRe: Using the MC9S12 MMC to force hardware reset line to be pulled.

Using the MC9S12 MMC to force hardware reset line to be pulled.

gman8 — Fri, 06 Mar 2015 03:42:26 GMT

The MMC can pull the hardware reset line on a bad memory request, however I can not seem to make it work. I tried doing it using Xgate. Still no dice.

I need to perform a hardware reset without using the COP. Please give a specific example using 'C'. Thanks

Re: Using the MC9S12 MMC to force hardware reset line to be pulled.

iggi — Fri, 13 Mar 2015 14:18:16 GMT

Hi,

I assume you mean generation of system reset when CPU accesses an unimplemented address (i.e., an address which does not belong to any of the on-chip modules).

For example, you can try to read or write to a global address of your device memory map which is unimplemented.

/* S12XEP100 device */

void main (void)

{

unsigned char data3, data4;

// Unimplemented RAM area

data3 = *(unsigned char *far)0x000800;

(void) data3;

// Unimplemented FLASH area

data4 = *(unsigned char *far)0x400000;

(void) data4;

}

After this, ILAF flag is set which is unaffected by system reset. It can be cleared by writing a 1 to CRGFLG register, or cleared by power on or low voltage reset.

Regards,

Ivan

Re: Using the MC9S12 MMC to force hardware reset line to be pulled.

HSW — Mon, 16 Mar 2015 13:02:35 GMT

Hello Gary,

Illegal address resets can only be triggered by the CPU. Illegal accesses performed by the XGATE will result in "XGATE Software Error" interrupts.