Other Parts Discussed in Thread: LMX2594EVM
Hi, I am trying to do PLL lock using SPI thorugh STM microcontoller for LMX2572, i am facing an issue to lock PLL where i am using 125 MHz (Fosc) and trying to calibtrate the using the sequence given in the data sheet. where i have reset the R0 register bit 1 to high(1) and then wrote the following sequence in code to lock the PLL:
R0 = 0x221E,
R36 = 0x240030,
R84 = 0x540001,
R85 = 0x55D800,
R82 = 0x522800,
R80 = 0x50CCCC,
R79 = 0x4F004C,
R100 = 0x642710,
R104 = 0x682710,
R0 = 0x219C.
here is the sample how i wrote in code for R80:
HAL_Delay(20);
txBuff[0] = 0x50; txBuff[1] = 0xCC; txBuff[2] = 0xCC; //R80
HAL_GPIO_WritePin(GPIOA, CSB_PLL_Pin, RESET);
HAL_SPI_Transmit(&hspi2,txBuff,1,HAL_MAX_DELAY) //Address
HAL_SPI_Transmit(&hspi2,&txBuff[1],2,HAL_MAX_DELAY) //Data
HAL_GPIO_WritePin(GPIOA, CSB_PLL_Pin,SET);
HAL_Delay(20);
