Problem with SPI SCLK

smbov — Tue, 10 Jul 2018 06:57:41 GMT

Hi!,

Firstly, I want to say hellow to everyone because it is my first question in this forum. Thank you to everyone.

I want to use a SPI connection with the LPC824 but the problem is that although CPOL and CPHA are set to 0, the SCLK starts at low state but then, before y send a byte, it mantains a high state.

I let you the SPI startup code below:

///spi
Init_SPI_PinMux();

Chip_GPIO_Init(LPC_GPIO_PORT);
Chip_GPIO_SetPinDIROutput(LPC_GPIO_PORT,0,PIN_psel);
Chip_GPIO_SetPinDIRInput(LPC_GPIO_PORT,0,PIN_busy);
Chip_GPIO_SetPinDIRInput(LPC_GPIO_PORT,0,PIN_irq);
Chip_GPIO_SetPinState(LPC_GPIO_PORT,0,PIN_psel,true);

Chip_SPI_Init(LPC_SPI1);
Chip_SPI_ConfigureSPI(LPC_SPI1, SPI_MODE_MASTER | /* Enable master/Slave mode */
SPI_CLOCK_CPHA0_CPOL0 | /* Set Clock polarity to 0 */
SPI_CFG_MSB_FIRST_EN |/* Enable MSB first option */
SPI_CFG_SPOL_LO); /* Chipselect is active low */

Thank you

Re: Problem with SPI SCLK

smbov — Tue, 10 Jul 2018 09:34:59 GMT

Finally, I could found the problem. I have to set the End Of Transfer Bit before each byte transfer.

LPC MicrocontrollersのトピックProblem with SPI SCLK

Problem with SPI SCLK

Re: Problem with SPI SCLK