如何配置寄存器，才能使DS90UB927Q-Q1内部时钟输出测试信号到DS90UB926Q-Q1？

现在采用DS90UB927Q-Q1输出到DS90UB926Q-Q1，只连接了FPD-Link III双绞线。
请问，该如何配置寄存器，使DS90UB927Q-Q1 内部时钟输出测试信号到DS90UB926Q-Q1。
我现在使用AN-2198介绍的代码，不能显示，请各位帮忙看下哪里有问题，谢谢!
ds927_write_reg(client,0x66,0x03);
ds927_write_reg(client,0x67,0x06);
ds927_write_reg(client,0x66,0x07);
ds927_write_reg(client,0x67,0x20);
ds927_write_reg(client,0x66,0x08);
ds927_write_reg(client,0x67,0x03);
ds927_write_reg(client,0x66,0x1E);
ds927_write_reg(client,0x67,0x09);
ds927_write_reg(client,0x66,0x04);
ds927_write_reg(client,0x67,0x98);
ds927_write_reg(client,0x66,0x05);
ds927_write_reg(client,0x67,0xD4);
ds927_write_reg(client,0x66,0x06);
ds927_write_reg(client,0x67,0x20);
ds927_write_reg(client,0x66,0x0C);
ds927_write_reg(client,0x67,0xD8);
ds927_write_reg(client,0x66,0x08);
ds927_write_reg(client,0x67,0x23);
ds927_write_reg(client,0x65,0x17);
ds927_write_reg(client,0x64,0x11);