Unable to generate interrupt from SBC!

[vaibhav_sharma]

Hi,

SBC- FS6513C: How to generate a test case to check the working of interrupt? I've tried to reduce the power supply down to 2V which should fulfill the 1st category depicted below.

Have tried other options as well, like voltage change(0-12V) on IO_0 line, which should fall under the category of IO_0 digital state change. I've tried inserting wrong parity(SPI_PARITY) & SPI_REQ as well. But all these couldn't get me trigger on INTB pin.

Values of INT registers configured-

0x8A06, // INIT_INH_INT
0x8800, // INIT_INT

Have I missed anything or, if not, then how to generate a test case to verify the INTB?

[DennisZeng]

Hi, Vaibhav 

There are no special requirement for INTB pin.  INTB is internal pull up to VDDIO.  When some event happen on FS65, INTB will have low pulse with 100us(default).  Pls use scope to capture the INTB pulse.

I suggest you use below event to trigger INTB pulse.

[vaibhav_sharma]

Hi Dennis,

Thanks for responding.

I've already tried the above case. I reduced the input voltage to SBC to 1V, but the INTB line is high only(verified on scope); no pulse was generated. What could be the reason?

[DennisZeng]

Hi, Vaibhav 

How many boards have this phenomenon? 

Pls. make sure the INTB event is not mask in SPI register. 

Br

Dennis 

[vaibhav_sharma]

Hi Dennis,

I have checked it on two sample ECUs. Interrupt is only getting generated for CANH_BATT diagnostic bit(NOT deliberately inserted).

The INIT_INT register is having the default value; which is given in my question as well, not inhibiting any of the interrupt event/generation.

[vaibhav_sharma]

Hi Dennis,

Any findings?

[DennisZeng]

Hi, Vaibhav 

No, it is strange behavior. Do you mind to share schematic with us?  We can check it.

My mail address: jianping.zeng@nxp.com

Br

Dennis Zeng

[vaibhav_sharma]

Hi Dennis,

Currently, the SBC is configured with buck-boost converter. So, maybe it is maintaining the voltage even if the battery voltage is decreased to such extent. Can this be the possibility?

As user manual states, 
•When VSUP > VSUP_UV_7, the converter works in buck mode and the VPRE output is regulated at 6.5 V typ.
•When VSUP < VSUP_UV_7, the converter works in boost mode and the VPRE output is regulated at 6.3 V typ.

It doesn't generate any interrupt till bearable instance & then below 3V, I am getting Vcore switched off(debugger shows power fail error).