ecore_calc_cdu_validation_byte
*x_val_ptr = ecore_calc_cdu_validation_byte(ctx_type, 3, cid);
*t_val_ptr = ecore_calc_cdu_validation_byte(ctx_type, 4, cid);
*u_val_ptr = ecore_calc_cdu_validation_byte(ctx_type, 5, cid);
*region1_val_ptr = ecore_calc_cdu_validation_byte(ctx_type, 1, tid);