[LPC4357] Enable RTC and show the time on display panel using emWin function, and then the system crashed.

[lpcware]

Content originally posted in LPCWare by wangchainh on Tue Apr 02 02:07:07 MST 2013
Hi guys,
I have a question about using the rtc and emwin.
Software:
Code base on LPC open 1.01.
emWin 518 1.00
Hardware:
LPC4357 Demo board

I modified the project hello_world, and show some strings or show a jpg/gif/bmp on display panel. It is no any problem. (Path: ..\lpcopen\applications\lpc18xx_43xx\examples\emWin\emwin_hello_world)

I modified the project hello_world, and enable RTC. RTC can work well. I can print the time via USARE 3. (RTC code copy from .. \lpcopen\applications\lpc18xx_43xx\examples\periph\periph_rtc)

But, I enabled the RTC and then called any emWin function. The system will crash.
Somebody know why?

PS: hello_world have enabled two framebuffer.

[lpcware]

Content originally posted in LPCWare by lturcotte on Thu Jan 16 15:50:27 MST 2014
I encounter a similar problem
For the benefit of others, here is my solution.

From LPC open, file: clock_18xx_43xx.c

the Chip_Clock_RTCEnable was reprogramming the CLK0 pin
CLK0 is used for the SDRAM interface.

/* Enable RTC Clock */
void Chip_Clock_RTCEnable(void)
{
LPC_CREG->CREG0 &= ~((1 << 3) | (1 << 2));/* Reset 32Khz oscillator */
LPC_CREG->CREG0 |= (1 << 1) | (1 << 0);/* Enable 32 kHz & 1 kHz on osc32k and release reset */
// conflict with SDRAM clock pin, do not reprogram clock pin
//LPC_SCU->SFSCLK[0] = 1 | (0x3 << 2);/* function 1; CGU clk out, pull down */
}