Hi @liyongfeng,
I do not see the initialization for the second core inside the project for core0. Can you share it? It should look something like this:
void Start_Core(void)
{
IP_MC_ME->PRTN0_CORE4_PCONF &= ~(1 << MC_ME_PRTN0_CORE4_PCONF_CCE_SHIFT);
IP_MC_ME->PRTN0_CORE4_PUPD = 1;
IP_MC_ME->CTL_KEY = 0x5AF0;
IP_MC_ME->CTL_KEY = 0xA50F;
while ((IP_MC_ME->PRTN0_CORE4_STAT & MC_ME_PRTN0_CORE4_STAT_CCS_MASK) == 1)
;
IP_MC_ME->PRTN0_CORE4_ADDR = (uint32)&__CORE2_VTOR;
IP_MC_ME->PRTN0_CORE4_PCONF |= (1 << MC_ME_PRTN0_CORE4_PCONF_CCE_SHIFT);
IP_MC_ME->PRTN0_CORE4_PUPD = 1;
IP_MC_ME->CTL_KEY = 0x5AF0;
IP_MC_ME->CTL_KEY = 0xA50F;
while ((IP_MC_ME->PRTN0_CORE4_STAT & MC_ME_PRTN0_CORE4_STAT_CCS_MASK) == 0)
;
}
Do you have CM7_1_ENABLE symbol inside project settings?

I've also sent you a private message for an example routine and training presentation for multicore debugging and single elf.
Best regards,
Julián