[C10] Thông báo buổi học 19-4-2014

[messier]

Ngày mai (19-4-2014) chúng ta sẽ tìm hiểu về Capacitive Touch với MSP430. Phòng học tại 201B1 vào lúc 14h00.
1. Các bạn cần làm module Capacitive Touch trong file đính kèm: Link
2. Slide bài học cho ngày mai: Slide .
Update source code cho bữa nay: (nhớ chọn project properties->advance option->language option->Enable gcc extension).

#include <msp430g2553.h>
#define WDT_meas_setting    (WDT_MDLY_8)        // watchdog interval = 0.5 ms
 
static unsigned int base_cap[4];                // Baseline capacitance for each pad
 
struct Element{                                    // This structure contains informations of sensor pad
    unsigned char *Pxsel;                        // Pointer to Pxsel register
    unsigned char *Pxsel2;                        // Pointer to Pxsel2 register
    unsigned char *Pxdir;                        // Pointer to Pxdir register
    unsigned char *Pxout;                        // Pointer to Pxout register
    unsigned char inputBits;                    // Input bit
    unsigned int *baseline;                                // Pointer to baseline capacitance
};
//*************************************************************************
// Define sensor pad element
//*************************************************************************
const struct Element KEY_1 = {
        .Pxsel = (unsigned char *)&P2SEL,
        .Pxsel2 = (unsigned char *)&P2SEL2,
        .Pxdir = (unsigned char *)&P2DIR,
        .inputBits = BIT0,
        .baseline = &base_cap[0]
};
 
const struct Element KEY_2 = {
        .Pxsel = (unsigned char *)&P2SEL,
        .Pxsel2 = (unsigned char *)&P2SEL2,
        .Pxdir = (unsigned char *)&P2DIR,
        .inputBits = BIT1,
        .baseline = &base_cap[1]
};
 
const struct Element KEY_3 = {
        .Pxsel = (unsigned char *)&P2SEL,
        .Pxsel2 = (unsigned char *)&P2SEL2,
        .Pxdir = (unsigned char *)&P2DIR,
        .inputBits = BIT2,
        .baseline = &base_cap[2]
};
 
const struct Element KEY_4 = {
        .Pxsel = (unsigned char *)&P2SEL,
        .Pxsel2 = (unsigned char *)&P2SEL2,
        .Pxdir = (unsigned char *)&P2DIR,
        .inputBits = BIT3,
        .baseline = &base_cap[3]
};
 
const struct Element *KEY[] = {&KEY_1, &KEY_2, &KEY_3, &KEY_4};    // Define Element pointer array
unsigned int measure_count(const struct Element *pad);
//*************************************************************************
// Program subroutines
//*************************************************************************
void base_calib(void){                        // Measure the baseline capacitance each pad
    char i = 3;
    do{
        base_cap[i] = measure_count(KEY[i]);
    }while(i--);
}
//------------------------------------------------------------------------
/* Measure raw count */
unsigned int measure_count(const struct Element *pad){
    int meas_cnt;
    TA0CTL = TASSEL_3 + MC_2;              // TACLK, continous mode
    TA0CCTL1 = CM_3 + CCIS_2 + CAP;        // Pos & Neg, GND, capture mode
 
    *(pad->Pxsel) &= ~pad->inputBits;            // TACLK input
    *(pad->Pxsel2) |= pad->inputBits;
    *(pad->Pxdir) &= ~pad->inputBits;            // input pins
 
    /*Setup Gate Timer*/
    WDTCTL = WDT_meas_setting;              // WDT, SMCLK, interval timer
    TA0CTL |= TACLR;                        // Clear Timer_A TAR
    _bis_SR_register(LPM0_bits+GIE);      // Wait for WDT interrupt
    meas_cnt = TA0CCR1;                    // Save result
    WDTCTL = WDTPW + WDTHOLD;              // Stop watchdog timer
    TA0CTL = MC_0;                            // Stop timer0
    *(pad->Pxsel2) &= ~pad->inputBits;
    return meas_cnt;
}
//------------------------------------------------------------------------
//*************************************************************************
// Main Program
//*************************************************************************
void main(void) {
    volatile int delta_count;
    WDTCTL = WDTPW | WDTHOLD;                // Stop watchdog timer
    BCSCTL1 = CALBC1_16MHZ;                // Set DCO to 1MHz
    DCOCTL =  CALDCO_16MHZ;
 
    IE1 |= WDTIE;                          // Enable WDT interrupt
    base_calib();
    while(1){
        delta_count = *(KEY_2.baseline) - measure_count(&KEY_2);
        if(delta_count > 15){                // If Key 2 is touched -> turned on LED 1
            P1DIR |= BIT0;
            P1OUT |= BIT0;
        }
        else P1OUT &= ~BIT0;
 
        delta_count = *(KEY_3.baseline) - measure_count(&KEY_3);
        if(delta_count > 20){                // If Key 2 is touched -> turned on LED 2
            P1DIR |= BIT6;
            P1OUT |= BIT6;
        }
        else P1OUT &= ~BIT6;
    }
 
}
 
//*************************************************************************
// Interrupt service routine
//*************************************************************************
#pragma vector=WDT_VECTOR
__interrupt void watchdog_timer(void)
{
    TA0CCTL1 ^= CCIS0;                        // Toggle CM0 to initiate capture
    _bic_SR_register_on_exit(LPM3_bits);  // Exit LPM3 on reti
}
 
#pragma vector=ADC10_VECTOR,COMPARATORA_VECTOR,NMI_VECTOR,PORT1_VECTOR, PORT2_VECTOR, TIMER0_A0_VECTOR, TIMER0_A1_VECTOR, TIMER1_A0_VECTOR, TIMER1_A1_VECTOR, USCIAB0RX_VECTOR, USCIAB0TX_VECTOR
__interrupt void Trap_isr(void){
    while(1){
        _bis_SR_register(LPM4_bits);
    }
}

 

[messier]

Đã update source code

 

[Phạm Thành Danh]

code này k có phần hiệu chỉnh Base_calib hả anh

 

[mafiaWolf]

Nếu không lầm thì mình có thể chỉnh độ nhạy bằng cách thay đổi cái giá trị so sánh delta_count á
Nếu sai thì ném đá nhẹ nhẹ thôi nha