请问用XMC4700- F100K的P14.5 VADC G0CH5进行AD输入为什么没有结果呢？

void brakeadc_init(void)
{
VADC_G0->ARBCFG= 0x00000003; //The Arbitration Configuration Register selects the timing and the behavior of the arbiter.
while(VADC_G0->ARBCFG   0x10000000){} //wait for start up calibration complete


VADC_G0->ARBPR |= 0x0700000a; //

VADC_G0->QINR0 |= 0x25; //


VADC_G0->QCTRL0 |= 0xc800;


VADC_G0->QMR0 |= 0x05;

VADC_G0->CHCTR[5] |= 0x00050000; //结果寄存器保存到G0RES0
VADC_G0->RCR[1] |= 0x80000000;

}
这是对P14.5脚 ADC G0 CH5进行AD初始化，读VADC_G0->RES[5]这个结果寄存器一直是0，请问配置哪个地方不对？谢谢