MPC5606 复位源判断

[yangyulong]

我想判断5606是否是由于看门狗（SWT）触发复位，尝试读取了不同情况下的RGM_*相关寄存器，各标志位没有明显变化。5606是否支持复位源判断，有相关示例代码可以参考一下吗。

[lukaszadrapa]

Hi,

important point is that RGM_FES and RGM_DES registers are cleared only on Power-On reset. So, to get relevant information, it is necessary to follow this sequence:

- read RGM_DES and RGM_FES after each reset.

- clear all the flags in RGM_DES and RGM_FES by writing '1'. You can simply write the registers like RGM_DES = 0xFFFFFFFF and RGM_FES = 0xFFFFFFFF

- ... and wait for reset...

Then you will get appropriate result after each reset.

Regards,

Lukas

[yangyulong]

We has try to w1c the status register,but the software reset and SWT reset will trigger same flag been set.

How to distinguish between the two cases way to? 

[lukaszadrapa]

It looks like a reset was triggered before the flag clearing, so two flags are set. I would check this by an oscilloscope if you can see two resets on the reset line.

Regards,

Lukas

[yangyulong]

This is SWT reset, and register value:

RGM_FES:0x80

RGM_DES:0x00

This is software reset, and register value:

RGM_FES:0x80

RGM_DES:0x00

[lukaszadrapa]

This doesn't make sense, value 0x80 in RGM_FES means that F_LVD45 flag is set (Flag for 4.5 V low-voltage detected).

Which device do you have exactly? Is that MPC5606S or MPC5606B?

Regards,

Lukas

[yangyulong]

The MPC5606B device used.

[lukaszadrapa]

I can see no problem on my side. If I generate SW reset, F_SOFT is set. If watchdog is not disabled, F_SWT is set after reset when it expires.

I would need to see more details what you do exactly.

Regards,

Lukas

[yangyulong]

We need to be able to distinguish the cause of system reset by reading one or some column flag bits.

[yangyulong]

Where the F_SOFT and F_SWT description in the 5606 user manual? We try to search the key word, but noting can find.

[yangyulong]

We just built a simple test logic to trigger software reset or stop watchdog feeding through can message. After entering the program, read the flag bit and clear it.

[lukaszadrapa · Accepted solution]

There are two reference manuals:

One covering MPC5605BK and MPC5606BK (you have obviously this one):

https://www.nxp.com/webapp/Download?colCode=MPC5606BRM

And second one is covering MPC5605B, MPC5606B and MPC5607B:

https://www.nxp.com/webapp/Download?colCode=MPC5607BRM

The differences between MPC5606B and MPC5606BK are described in:

https://www.nxp.com/docs/en/application-note/AN4477.pdf

Which part number do you have exactly?

In any case, it is obviously a documentation issue in the version for MPC5606BK. Thanks for pointing this out, I will report it. You can take a look to the second manual where it is described correctly.

By the way, I saw that you mentioned on 8bit number like 0x80 in previous posts. Maybe this is the source of misunderstanding - it's 16bit register.

Regards,

Lukas

[yangyulong]

You are right. Our document has issue.This is my manual register description：

Referring to the register definition you provided , we can  distinguish the reset source.

Thanks.