how to read cause of reset on PSoC6 (Cy8C6347)

[TeMa_1467596]

I have PSoC Creator 4.2 C code running for both cores in a dual core project for PSoC6 (CY8C6347BZI) and the cm0p core is the master.  As the system boots (or reboots) I need to have code examine the cause of the last reboot.  I have found register RES_CAUSE in TRM (page 581) with definition of bits and what they mean but I'm struggling to come up with the code to read that register.

Any chance of a few lines of example code to read this register so I can take actions based on the cause of the reset?

Thanks,

Ted

[Len_CONSULTRON · Accepted solution]

Ted,

Instead of calling RES_CAUSE register directly, use the following call instead:

/*******************************************************************************
* Function Name: Cy_SysLib_GetResetReason
****************************************************************************//**
*
* The function returns the cause for the latest reset(s) that occurred in
* the system. The reset causes include an HFCLK error, system faults, and
* device reset on a wakeup from Hibernate mode.
* The return results are consolidated reset causes from reading RES_CAUSE,
* RES_CAUSE2 and PWR_HIBERNATE token registers.
*
* \return The cause of a system reset.
*
* | Name                          | Value
* |-------------------------------|---------------------
* | CY_SYSLIB_RESET_HWWDT         | 0x00001 (bit0)
* | CY_SYSLIB_RESET_ACT_FAULT     | 0x00002 (bit1)
* | CY_SYSLIB_RESET_DPSLP_FAULT   | 0x00004 (bit2)
* | CY_SYSLIB_RESET_CSV_WCO_LOSS  | 0x00008 (bit3)
* | CY_SYSLIB_RESET_SOFT          | 0x00010 (bit4)
* | CY_SYSLIB_RESET_SWWDT0        | 0x00020 (bit5)
* | CY_SYSLIB_RESET_SWWDT1        | 0x00040 (bit6)
* | CY_SYSLIB_RESET_SWWDT2        | 0x00080 (bit7)
* | CY_SYSLIB_RESET_SWWDT3        | 0x00100 (bit8)
* | CY_SYSLIB_RESET_HFCLK_LOSS    | 0x10000 (bit16)
* | CY_SYSLIB_RESET_HFCLK_ERR     | 0x20000 (bit17)
* | CY_SYSLIB_RESET_HIB_WAKEUP    | 0x40000 (bit18)
*
* \note CY_SYSLIB_RESET_CSV_WCO_LOSS, CY_SYSLIB_RESET_HFCLK_LOSS and
*       CY_SYSLIB_RESET_HFCLK_ERR causes of a system reset available only if
*       WCO CSV present in the device.
*
*******************************************************************************/
uint32_t Cy_SysLib_GetResetReason(void)

It takes care of all the messy bits and is controlled by Cypress if changes are needed in the future.

Suggestion:  Perform the Cy_SysLib_GetResetReason() as the first line of text in main().

Len

[TeMa_1467596]

Thanks, I added a uint32 and then this line...

rebootCode = Cy_SysLib_GetResetReason();

and it seems to work, a normal startup gives zero and NVIC_SystemReset(); gives 16

Thanks for your help Len

Ted