Part Number: TM4C129XNCZAD
Tool/software: Code Composer Studio
Hi,
I have some problems on SSI of TM4C129XNCZAD. The SSI is set as master, when transmitting data, the SSI do not work. The pin CSn keep high, and the pin clock do not change. The code are as below.
ui32SysClock = SysCtlClockFreqSet((SYSCTL_XTAL_25MHZ | SYSCTL_OSC_MAIN | SYSCTL_USE_OSC), 25000000);
SysCtlPeripheralEnable(SYSCTL_PERIPH_SSI0);
SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOA);
GPIOPinConfigure(GPIO_PA2_SSI0CLK);
GPIOPinConfigure(GPIO_PA3_SSI0FSS);
GPIOPinConfigure(GPIO_PA4_SSI0RX);
GPIOPinConfigure(GPIO_PA5_SSI0TX);
GPIOPinTypeSSI(GPIO_PORTA_BASE, GPIO_PIN_5 | GPIO_PIN_4 | GPIO_PIN_3 | GPIO_PIN_2);
SSIConfigSetExpClk(SSI0_BASE, ui32SysClock, SSI_FRF_MOTO_MODE_0,SSI_MODE_MASTER, 1000000, 8);
SSIEnable(SSI0_BASE);
while(SSIDataGetNonBlocking(SSI0_BASE, &pui32DataRx[0]))
{
}
pui32DataTx[0] = 's';
pui32DataTx[1] = 'p';
pui32DataTx[2] = 'i';
for(ui32Index = 0; ui32Index < NUM_SSI_DATA; ui32Index++)
{
SSIDataPut(SSI0_BASE, pui32DataTx[ui32Index]);
}
while(SSIBusy(SSI0_BASE))
{
}
for(ui32Index = 0; ui32Index < NUM_SSI_DATA; ui32Index++)
{
SSIDataGet(SSI0_BASE, &pui32DataRx[ui32Index]);
pui32DataRx[ui32Index] &= 0x00FF;
}
When running to the code 'SSIDataPut(SSI0_BASE, pui32DataTx[ui32Index])', all the SSI pins on chip do not change, and the register of SSIDR keeps zeros, and register SSISR keeps 0x3.
What's wrong about the code?
Thank you
