MAX_STACK
" sizeof(struct trapframe) %d byte\n", MAX_STACK, MAX_FRAME,
t32 = (uint32_t *)(pcb->pcb_sf.sf_r7_bank - MAX_STACK);
i = MAX_STACK - i * sizeof(int);
pcb->pcb_sf.sf_r7_bank, i, i * 100 / MAX_STACK,