DAC61416芯片供电正常，VIO 1.8V， VAA VDD 5.0V，VCC +12.2V，VSS -12.2V，SPI通信已通过读取DEVICEID验证正常，需输出方波电压（非差分），按照数据手册进行编程（简要代码如下），实际输出为0，请帮忙解答
//Power-on Device, Disable Soft-toggle, Set Streaming Mode,Power-on Internal Reference
SPI_Transmit 0x03(***),0x0A,0x8C
SPI_Transmit 0x04(GENCONFIG),0x3F,0x00
//Select Range for all the channels as ±10V
SPI_Transmit 0x0A(DACRANGE0),0xAA,0xAA,0xAA,0xAA,0xAA,0xAA,0xAA,0xAA
//Power-on DAC Channels
SPI_Transmit 0x09(DACPWDWN),0x00,0x00
//Set DAC channel in synchronous mode and disable toggle mode for that channel
SPI_Transmit 0x06(SYNCCONFIG),0xFF,0xFF
SPI_Transmit 0x07(TOGGCONFIG0),0x00,0x00,0x00,0x00
//Write Positive voltage code to Register A
SPI_Transmit 0x10(DAC0),0xXX,0xXX,0xXX,0xXX..
数据如0x91,0x60,0x91,0xA0,0x92,0x50...
//Issue a DAC trigger signal to load Register A
LDAC引脚拉低
//Write Negative voltage code to Register B
SPI_Transmit 0x10(DAC0),0xXX,0xXX,0xXX,0xXX..
//Enable toggle mode to load Register B
SPI_Transmit 0x07(TOGGCONFIG0),0x55,0x55,0x55,0x55
//Input PWM
MCU发送PWM信号给TOGGLE0引脚
