NANO100:Using data flash without the external 12M HZ crystal.

The data flash start address is set by register so it need a reset after update the address, but in default it will use  the external 12M HZ crystal.It's need to modify the CFOSC .

Modify the \SampleCode\StdDriver\FMC_RW set_data_flash_base() function

	static int set_data_flash_base(uint32_t u32DFBA)
	{
	uint32_t au32Config[2];
	if (FMC_ReadConfig(au32Config, 2) < 0) {
	printf("\nRead User Config failed!\n");
	return -1;
	}
	if ((!(au32Config[0] & 0x1)) && (au32Config[1] == u32DFBA))
	return 0;
	FMC_ENABLE_CFG_UPDATE();
	au32Config[0] &= ~0x1;
	au32Config[0] |= 0x1<<26; //Enable the HIRC
	au32Config[1] = u32DFBA;
	if (FMC_WriteConfig(au32Config, 2) < 0)
	return -1;
	printf("\nSet Data Flash base as 0x%x.\n", DATA_FLASH_TEST_BASE);
	// Perform chip reset to make new User Config take effect
	SYS->IPRST_CTL1 = SYS_IPRST_CTL1_CHIP_RST_Msk;
	return 0;
	}

view raw gistfile1.txt hosted with ❤ by GitHub

Ref:
     Nano100 Series Technical Reference Manual

NANO100:Enable printf use Nu-Link to send massage

1.Add #define DEBUG_ENABLE_SEMIHOST in Library\StdDriver\src\retarget.c .
 

2.Start Keil C IDE debug session and enable the View\Serial Windows\UART #1.

3. Now you can see the printf massage in Keil C IDE.

Ref:

   1. Nuvoton Nu-Link Debug Adapter

   2. Semihosting

Octave: Modulation Sine Wave use PWM generate look up table for MCU DAC.

Input the target sample frequency ,sample bits and sample frequency.Generate the duty of PWM(percentage).
Code:

	clc;
	clear;
	sample_bits = 12;#smaple bits
	fs = 10000; #sample frequency
	f = 60; #target frequency
	amp= 2^(sample_bits-1);
	t = 0:1/fs:1/f;
	x = amp*(1+sin(2*pi*f*t));#avoid negative part
	pwm_duty = x/(amp*2);
	bar (pwm_duty);

view raw PWM_SINE.m hosted with ❤ by GitHub

Avoid the negative part cause normally MCU didn't have negative voltage output ability.







Ref:
    1.http://bugworkshop.blogspot.tw/2011/04/blog-post_12.html