|
Hello, I'm a student of the University in Zielona Ga in Poland. I have a little problem with using plug-in software for THS1206evm. I wrote very simple program using THS1206evm with TMS320C6711 (under CCS 1.23) which does pwm control In this program I compare triangle with input signal (first channel of THS1206evm device). If input signal > triangle then the LED_1 is swiched on else the LED_1 is swiched off. LED_2 is swiched on/off after reading 256 samples. I met with the following problem: I set the freq=6 MHz (ths1206evm) so the frequency LED_2 should be about 23.44 kHz`00kHz/256 but when I measure using osciloscope notice that is 1 kHz. I don't know why? I must do pwm at least about 30 kHz . I don't know where I did mistake. Maybe I should try to use timers? Here is my program: #include "dc_conf.h" #include "t1206_fn.h" #include <stdio.h> #include <csl.h> #include <bsl.h> #include <bsl_led.h> #include <irq.h> #include <timer.h> #include <emif.h #define BLOCK_SZ 256 TIMER_HANDLE init_timer0(unsigned int period); void init_dsk(void); short ad_buffer[BLOCK_SZ]; float valuef[BLOCK_SZ]; /*input signal*/ float triangle[BLOCK_SZ]; float out[BLOCK_SZ]; int change=1; int control=1; int cnt=0; void main(void) { int i; TIMER_HANDLE hTimer; CSL_Init(); hTimer = init_timer0(ADC1_TIM_PERIOD); init_dsk(); dc_configure(&Ths1206_1); TIMER_Start(hTimer); IER=0x00000012; LED_off(LED_ALL); for (;;) { for (i=0; i<BLOCK_SZ; i++) { if (i==0) control=-control; if (control==1) LED_on(LED_2); if (control==-1) LED_off(LED_2); if (i<64) {change=1;}; if (i>63&i<128) {change=2;}; if (i>127&i<192) {change=3;}; if (i>191) {change=4;}; ad_buffer[i]=ths1206_read(&Ths1206_1); valuef[i]=(ad_buffer[i]-2048)*0.00048852-0.04; if (change==1) triangle[i]=0.032*i-1; if (change==2) triangle[i]=-0.032*(i-64)+1; if (change==3) triangle[i]=0.032*(i-128)-1; if (change==4) triangle[i]=-0.032*(i-192)+1; if (valuef[i]>triangle[i]) { out[i]=0; LED_on(LED_1); } if (valuef[i]<triangle[i]) { out[i]=1; LED_off(LED_1); } } } } Sorry for my mistakes. Regards, Poul |
THS1206evm and TMS320C6711 - pwm control
Started by ●August 13, 2002
