MPR121触摸芯片驱动代码调试

用飞思卡尔的MPR121做触摸按键键盘，在调试的过程中被虐得很惨，MPR121的寄存器太多，把一个应该简单易用的做得那么复杂，有点让人郁闷。
下面是在官方网上找到的初始化代码：

#define TouchThre 10//15//30//10
#define ReleaThre 8//8//25//8
void MPR121_init(void)
{
//Reset MPR121 if not reset correctly
IIC_ByteWrite(0x80,0x63); //Soft reset
IIC_ByteWrite(0x5E,0x00); //Stop mode
//touch pad baseline filter
//rising
IIC_ByteWrite(0x2B,0x01); //0xFF// MAX HALF DELTA Rising
IIC_ByteWrite(0x2C,0x01); //0xFF// NOISE HALF DELTA Rising
IIC_ByteWrite(0x2D,0x00); // //0 NOISE COUNT LIMIT Rising
IIC_ByteWrite(0x2E,0x00); // DELAY LIMIT Rising
//falling
IIC_ByteWrite(0x2F,0x01); // MAX HALF DELTA Falling
IIC_ByteWrite(0x30,0x01); // NOISE HALF DELTA Falling
IIC_ByteWrite(0x31,0xFF); // NOISE COUNT LIMIT Falling
IIC_ByteWrite(0x32,0x02); // //2//DELAY LIMIT Falling
//touched
IIC_ByteWrite(0x33,0x00); // Noise half delta touched
IIC_ByteWrite(0x34,0x00); // Noise counts touched
IIC_ByteWrite(0x35,0x00); //Filter delay touched
//Touch pad threshold
IIC_ByteWrite(0x41,TouchThre); // ELE0 TOUCH THRESHOLD
IIC_ByteWrite(0x42,ReleaThre); // ELE0 RELEASE THRESHOLD
IIC_ByteWrite(0x43,TouchThre); // ELE1 TOUCH THRESHOLD
IIC_ByteWrite(0x44,ReleaThre); // ELE1 RELEASE THRESHOLD
IIC_ByteWrite(0x45,TouchThre); // ELE2 TOUCH THRESHOLD
IIC_ByteWrite(0x46,ReleaThre); // ELE2 RELEASE THRESHOLD
IIC_ByteWrite(0x47,TouchThre); // ELE3 TOUCH THRESHOLD
IIC_ByteWrite(0x48,ReleaThre); // ELE3 RELEASE THRESHOLD
IIC_ByteWrite(0x49,TouchThre); // ELE4 TOUCH THRESHOLD
IIC_ByteWrite(0x4A,ReleaThre); // ELE4 RELEASE THRESHOLD
IIC_ByteWrite(0x4B,TouchThre); // ELE5 TOUCH THRESHOLD
IIC_ByteWrite(0x4C,ReleaThre); // ELE5 RELEASE THRESHOLD
IIC_ByteWrite(0x4D,TouchThre); // ELE6 TOUCH THRESHOLD
IIC_ByteWrite(0x4E,ReleaThre); // ELE6 RELEASE THRESHOLD
IIC_ByteWrite(0x4F,TouchThre); // ELE7 TOUCH THRESHOLD
IIC_ByteWrite(0x50,ReleaThre); // ELE7 RELEASE THRESHOLD
IIC_ByteWrite(0x51,TouchThre); // ELE8 TOUCH THRESHOLD
IIC_ByteWrite(0x52,ReleaThre); // ELE8 RELEASE THRESHOLD
IIC_ByteWrite(0x53,TouchThre); // ELE9 TOUCH THRESHOLD
IIC_ByteWrite(0x54,ReleaThre); // ELE9 RELEASE THRESHOLD
IIC_ByteWrite(0x55,TouchThre); // ELE10 TOUCH THRESHOLD
IIC_ByteWrite(0x56,ReleaThre); // ELE10 RELEASE THRESHOLD
IIC_ByteWrite(0x57,TouchThre); // ELE11 TOUCH THRESHOLD
IIC_ByteWrite(0x58,ReleaThre); // ELE11 RELEASE THRESHOLD
//AFE configuration
IIC_ByteWrite(0x5D,0x00);
IIC_ByteWrite(0x5C,0xC0);
//Auto configuration
IIC_ByteWrite(0x7B,0xCB);
IIC_ByteWrite(0x7D,0xE4);
IIC_ByteWrite(0x7E,0x94);
IIC_ByteWrite(0x7F,0xCD);

IIC_ByteWrite(0x5E,0x0C);
}

代码的运行时正常，但是有几个问题：
1.感应距离太近，隔了一层亚克力板后感应就不灵敏了。
2.上面代码的配置不是低功耗模式，功耗达到300uA+，可以通过修改上面代码第49行IIC_ByteWrite(0x5D,0x00);中的第二个参数，改为IIC_ByteWrite(0x5D,0x06);时功耗降到11uA左右，第52到55行是配置为自动调节模式，在设置为自动模式时，对触摸阈值TouchThre  和释放阈值的ReleaThre设置没多少影响。
3.上电后，键盘有7-8秒的时间见内没有感应，这个问题在网上有很多都遇到了，有人在官网上提问题这个问题，也没看到有具体的回答。
官方的手册里也有明确讲到要则么设置芯片的这些寄存器。
由于上面那样的问题，我知道放弃使用MPR121触摸芯片的方案，而改用合泰的BS8116a-3，这个芯片的感应距离较远，只要键盘稍微大一点，5mm外就能感应到，但也会带来干扰问题，但可以通过减小键盘的尺寸和设置灵敏度来降低感应强度。