int
main(int argc, char **argv)
{
int frequency;
if (argc < 2) {
printf("Usage: %s <frequency>\n", argv[0]);
printf("Sets up a PWM signal on gpio 145 and 146 at the given frequency\n");
printf("and sweeps the duty-cycle up and down once\n");
exit(-1);
}
frequency = atoi(argv[1]);
int mem_fd = pwm_open_devmem();
if (mem_fd == -1) {
g_error("Unable to open /dev/mem, are you root?: %s", g_strerror(errno));
}
// Set instances 10 and 11 to use the 13 Mhz clock
pwm_config_clock(mem_fd, TRUE, TRUE);
guint8 *gpt10 = pwm_mmap_instance(mem_fd, 10);
guint8 *gpt11 = pwm_mmap_instance(mem_fd, 11);
// Get the resolution for 20 kHz PWM
guint32 resolution = pwm_calc_resolution(frequency, PWM_FREQUENCY_13MHZ);
printf("Resolution = %d\n", resolution);
// Ramp up and down a bit
int i;
for (i = 0; i <= 100; i++) {
g_print("%3d\n", i);
pwm_config_timer(gpt10, resolution, i / 100.0);
pwm_config_timer(gpt11, resolution, i / 100.0);
usleep(100000);
}
sleep(1);
for (i = 100; i >= 0; i--) {
g_print("%3d\n", i);
pwm_config_timer(gpt10, resolution, i / 100.0);
pwm_config_timer(gpt11, resolution, i / 100.0);
usleep(100000);
}
pwm_munmap_instance(gpt10);
pwm_close_devmem(mem_fd);
}
int start_pwm(int frequency, int duty_cycle){
int dev_fd;
unsigned int *PinConfig, *testValue;
unsigned int CurValue;
unsigned int *gpt10;
unsigned long resolution;
int i;
dev_fd = open("/dev/mem", O_RDWR | O_SYNC);
if (dev_fd == -1) {
printf("Can not opem /dev/mem.");
return -1;
}
// set the clock source to 13MHz
// comparing to GPIO/gpio.c, (unsigned int *) is added here
// so it then goes into int space and the offset (@char) must be devided by 4 (@int)
PinConfig = (unsigned int *) mmap(NULL, 0x300, PROT_READ | PROT_WRITE, MAP_SHARED, dev_fd, CM_CLOCK_BASE);
testValue = (volatile unsigned int*)(PinConfig+CM_CLKSEL_CORE/4);
CurValue = *(volatile unsigned int*)(PinConfig+CM_CLKSEL_CORE/4);
printf("The curvalue is CurValue %x\n", testValue);
CurValue &= 0xffffffbf;
CurValue |= 0x40; // set CLKSEL_GPT10 1,
*(volatile unsigned int*)(PinConfig+CM_CLKSEL_CORE/4) = CurValue;
printf("13MHz clock source enabled........\n");
// enable the clock: FCLK and ICLK
PinConfig = (unsigned int *) mmap(NULL, 0x300, PROT_READ | PROT_WRITE, MAP_SHARED, dev_fd, CM_CLOCK_BASE);
CurValue = *(volatile unsigned int*)(PinConfig+CM_FCLKEN1_CORE/4);
CurValue &= 0xfffff7ff;
CurValue |= 0x800; // set EN_GPT10 1, GPTIMER 10 functional clock is enabled
*(volatile unsigned int*)(PinConfig+CM_FCLKEN1_CORE/4) = CurValue;
printf("FCLOCK enabled........\n");
CurValue = *(volatile unsigned int*)(PinConfig+CM_ICLKEN1_CORE/4);
CurValue &= 0xfffff7ff;
CurValue |= 0x800; // set EN_GPT10 1, GPTIMER 10 interface clock is enabled
*(volatile unsigned int*)(PinConfig+CM_ICLKEN1_CORE/4) = CurValue;
printf("ICLOCK enabled.........\n");
munmap(PinConfig, 0x1000);
// System control module: 0x4800 2000, found via devmem2
PinConfig=(unsigned int *) mmap(NULL, 0x200, PROT_READ | PROT_WRITE, MAP_SHARED,dev_fd, 0x48002000);
// Set PWM function on pin: GPIO_56, EMA-product-board GPMC_nCS5, DM3730 spec page 2428
// division by 4 is necessary because the size of one element of "unsigned int" is 4 bytes, which corresponds to the size of control registers
CurValue=*(volatile unsigned int*)(PinConfig+0x174/4);
CurValue &= 0x0000ffff;
/* Timer 10: mode 2 - gpt_10_pwm_evt, PullUp selected, PullUp/Down enabled, Input enable value for pad_x */
CurValue |= 0x011A0000;
*(volatile unsigned int*)(PinConfig+0x174/4) = CurValue; //PIN CONFIGURED AS BIDIRECTIONAL
munmap(PinConfig, 0x200);
// Configure timer 10 and 11 to 13 MHz
// Config=(unsigned int *) mmap(NULL, 0x10000, PROT_READ | PROT_WRITE, MAP_SHARED,dev_fd, 0x48004000);
// CurValue=Config[0xA40/4];
// CurValue=CurValue | (1<<6) | (1<<7);
// CurValue |= (1<<6);//Configure 10 timer to 13 MHz
// CurValue |= (1<<7);//Configure 11 timer to 13 MHz
// Config[0xA40/4]=CurValue;
// GPTIMER10 base address: 0x48086000(in byte space)
// gpt10: in int space
gpt10=(unsigned int *) mmap(NULL, 0x10000, PROT_READ | PROT_WRITE, MAP_SHARED,dev_fd, 0x48086000);
resolution = pwm_calc_resolution(frequency, PWM_FREQUENCY_13MHZ);
pwm_config_timer(gpt10, resolution,duty_cycle);
munmap(gpt10, 0x10000);
close(dev_fd);
return 0;
}
int main(int argc, char *argv[]){
int dev_fd;
unsigned int *PinConfig;
unsigned int CurValue;
unsigned int *gpt10;
unsigned int *gpt11;
unsigned long resolution;
int i;
printf("Run like: sudo ./pwm_test 50\n");
//Configure PIN
dev_fd = open("/dev/mem", O_RDWR | O_SYNC);
if (dev_fd == -1) {
printf("Can not opem /dev/mem.");
return -1;
}
else
printf("dev_fd = %d...............\n", dev_fd);
//set the clock source to 13MHz
PinConfig = (unsigned int *) mmap(NULL, 0x300, PROT_READ | PROT_WRITE, MAP_SHARED,dev_fd, CM_CLOCK_BASE);
CurValue = INT(PinConfig+CM_CLKSEL_CORE/4);
CurValue &= 0xffffff3f;
CurValue |= 0xc0; //set CLKSEL_GPT10/11 1,
INT(PinConfig+CM_CLKSEL_CORE/4) = CurValue;
printf("13MHz clock source enabled........\n");
//enable the clock: FCLK and ICLK
PinConfig = (unsigned int *) mmap(NULL, 0x300, PROT_READ | PROT_WRITE, MAP_SHARED,dev_fd, CM_CLOCK_BASE);
CurValue = INT(PinConfig+CM_FCLKEN1_CORE/4);
CurValue &= 0xffffe7ff;
CurValue |= 0x1800; //set EN_GPT10/11 1, GPTIMER 10/11 functional clock is enabled
INT(PinConfig+CM_FCLKEN1_CORE/4) = CurValue;
printf("FCLOCK enabled........\n");
CurValue = INT(PinConfig+CM_ICLKEN1_CORE/4);
CurValue &= 0xffffe7ff;
CurValue |= 0x1800; //set EN_GPT10/11 1, GPTIMER 10/11 interface clock is enabled
INT(PinConfig+CM_ICLKEN1_CORE/4) = CurValue;
printf("ICLOCK enabled.........\n");
munmap(PinConfig, 0x1000);
//System control module: 0x4800 2000, found via devmem2
PinConfig=(unsigned int *) mmap(NULL, 0x200, PROT_READ | PROT_WRITE, MAP_SHARED,dev_fd, 0x48002000);
//Set PWM function on pin: GPIO_145/146, BB-xM-RevC P9-pin10/pin6
//division by 4 is necessary because the size of one element of "unsigned int" is 4 bytes, which corresponds to the size of control registers
CurValue=INT(PinConfig+0x174/4);
CurValue &= 0x0000ffff;
/* Timer 10: mode 2 - gpt_10_pwm_evt, PullUp selected, PullUp/Down enabled, Input enable value for pad_x */
CurValue |= 0x011A0000;
INT(PinConfig+0x174/4) = CurValue; //PIN CONFIGURED AS BIDIRECTIONAL
CurValue=INT(PinConfig+0x178/4);
CurValue &= 0xffff0000;
/* Timer 11: mode 2 - gpt_11_pwm_evt, PullUp selected, PullUp/Down enabled, Input enable value for pad_x */
CurValue |= 0x0000011A;
INT(PinConfig+0x178/4) = CurValue; //PIN CONFIGURED AS BIDIRECTIONAL
munmap(PinConfig, 0x200);
//Configure timer 10 and 11 to 13 MHz
//Config=(unsigned int *) mmap(NULL, 0x10000, PROT_READ | PROT_WRITE, MAP_SHARED,dev_fd, 0x48004000);
//CurValue=Config[0xA40/4];
//CurValue=CurValue | (1<<6) | (1<<7);
//CurValue |= (1<<6);//Configure 10 timer to 13 MHz
//CurValue |= (1<<7);//Configure 11 timer to 13 MHz
//Config[0xA40/4]=CurValue;
//GPTIMER10 base address: 0x48086000(in byte space)
//gpt10: in int space
gpt10=(unsigned int *) mmap(NULL, 0x10000, PROT_READ | PROT_WRITE, MAP_SHARED,dev_fd, 0x48086000);
resolution = pwm_calc_resolution(2000000, PWM_FREQUENCY_13MHZ);
pwm_config_timer(gpt10, resolution,atoi(argv[1]));
munmap(gpt10, 0x10000);
//gpt11: in int space
gpt11=(unsigned int *) mmap(NULL, 0x10000, PROT_READ | PROT_WRITE, MAP_SHARED,dev_fd, 0x4808000);
resolution = pwm_calc_resolution(2000000, PWM_FREQUENCY_13MHZ);
pwm_config_timer(gpt11, resolution,atoi(argv[1]));
munmap(gpt11, 0x10000);
close(dev_fd);
return 0;
}
