I have the simplest goal which is to send one little message to a DAC module.*To do this, what i need from chip select signal is to become low before transmit and then high when transmit ends.
I managed to do this with 2 different pin sets(test pins). But I failed to do this with the original pins(the ones that are connected in the PCB). Slave select signal stays at high all the time..
Then I tried to enable and disable it manually. To do this: I enable the transmit interrupt, I set Slave select IO to HIGH in the transmit interrupt(after all data bits are transferred) and LOW before transmit. But this method doesn't work either because
transmit interrupt is never received..
I want to remark that when I try this with other two pin sets, transmit interrupt works just fine.. I only change pins and stuff about them. I am adding my code..
Note: The pins that I am having trouble with can be seen above. The pin set that is totally OK is also there but commented.
#include "xmc_spi.h"
#include "GPIO.h"
#include "InterruptHandlerMap.h"
uint16_t DataReceived = 0;
void SPIReceive(void);
void SPITransmit(void);
// good pins
//#define PIN_MOSI P1_0
//#define PIN_SCLK P0_7
//#define PIN_SS P0_0
//XMC_USIC_CH_t* channel = XMC_SPI0_CH0;
//XMC_GPIO_MODE_t MOSIMode = XMC_GPIO_MODE_OUTPUT_PUSH_PULL_ALT7;
//XMC_GPIO_MODE_t SSMode = XMC_GPIO_MODE_OUTPUT_PUSH_PULL_ALT6;
//XMC_GPIO_MODE_t CLKMode = XMC_GPIO_MODE_OUTPUT_PUSH_PULL_ALT6;
// also good pins
//#define PIN_MOSI P1_2
//#define PIN_SCLK P1_4
//#define PIN_SS P1_1
//XMC_USIC_CH_t* channel = XMC_SPI0_CH1;
//XMC_GPIO_MODE_t MOSIMode = XMC_GPIO_MODE_OUTPUT_PUSH_PULL_ALT7;
//XMC_GPIO_MODE_t SSMode = XMC_GPIO_MODE_OUTPUT_PUSH_PULL_ALT7;
//XMC_GPIO_MODE_t CLKMode = XMC_GPIO_MODE_OUTPUT_PUSH_PULL_ALT2;
//bad pins
#define PIN_MOSI P2_13
#define PIN_SCLK P2_12
#define PIN_SS P4_0
XMC_USIC_CH_t* channel = XMC_SPI1_CH1;
XMC_GPIO_MODE_t MOSIMode = XMC_GPIO_MODE_OUTPUT_PUSH_PULL_ALT7;
XMC_GPIO_MODE_t SSMode = XMC_GPIO_MODE_OUTPUT_PUSH_PULL_ALT7;
XMC_GPIO_MODE_t CLKMode = XMC_GPIO_MODE_OUTPUT_PUSH_PULL_ALT4;
int main(void)
{
XMC_SPI_CH_CONFIG_t spi_config = { .baudrate = 10000,
.bus_mode = XMC_SPI_CH_BUS_MODE_MASTER,
.selo_inversion = XMC_SPI_CH_SLAVE_SEL_INV_TO_MSLS,
.parity_mode = XMC_USIC_CH_PARITY_MODE_ODD
};
XMC_SPI_CH_Init(channel, &spi_config);
XMC_SPI_CH_SetWordLength(channel, 16);
XMC_SPI_CH_SetFrameLength(channel, 16);
XMC_SPI_CH_SetBitOrderMsbFirst(channel);
//configureGPIO: calls XMC_GPIO_Init(..) inside
configureGPIO(PIN_MOSI, MOSIMode, GPIO_HIGH);
configureGPIO(PIN_SS, SSMode, GPIO_HIGH);
configureGPIO(PIN_SCLK, CLKMode, GPIO_HIGH);
XMC_USIC_CH_TXFIFO_Configure(channel, 0, XMC_USIC_CH_FIFO_SIZE_32WORDS, 0);
XMC_SPI_CH_EnableEvent(channel, XMC_SPI_CH_EVENT_TRANSMIT_SHIFT);
XMC_SPI_CH_SelectInterruptNodePointer(channel, XMC_SPI_CH_INTERRUPT_NODE_POINTER_TRANSMIT_SHIFT, 1);
XMC_SPI_CH_EnableSlaveSelect(channel, XMC_SPI_CH_SLAVE_SELECT_0);
XMC_SPI_CH_Start(channel);
registerIRQHandler(10, SPITransmit); // used to call SPITrasmit function in IRQ10_Handler()
NVIC_SetPriority(IRQ10_IRQn, 1U);
NVIC_EnableIRQ(IRQ10_IRQn);
/* Trigger manually the first interrupt */
SysTick_Config(SystemCoreClock / 1000);
while (1)
{
/* Infinite loop */
}
}
void SPITransmit(void)
{
//placed breakpoint in here but never hit with bad pin set
}
void SysTick_Handler()
{
static uint32_t tick = 0;
tick++;
if(500 == tick)
{
XMC_SPI_CH_Transmit(channel,1023, XMC_SPI_CH_MODE_STANDARD);
tick = 0;
}
}
