Problem generating PWM

[LukeVance5]

Hello,

I am currently trying to create an RC boat with this library. I have been usings Ikes example as a guide, and have been able to do the led blinking. I have also updated it to change led on keystroke from pc, which worked fine. Currently, I am having the issue that the reciever stops working when I enable a PWM on P1.2. I can no longer send commands from my transmitter, and the red led of failed transmission appears. The launchpad I am using is MSP430F5529LP. I thought I could change LPM4 to LPM0, but that didn't seem to work Here is my receiver code:

#include <msp430.h>
#include "intrinsics.h"
#include "msprf24.h"
#include "nrf_userconfig.h"
#include "stdint.h"

#define  TXD BIT4 // P4.4 - UART Transmitter
#define  RXD BIT5 // P4.5 - UART Receiver

volatile unsigned int user;
void init_rudder(void);
void rudder_left(void);
void rudder_right(void);
void main()
{
    char addr[5] = "00005";
    char buf[32];

    WDTCTL = WDTHOLD | WDTPW;

    // Red LED will be our output
    P1DIR |= BIT0;
    P4DIR |= BIT7;
    P1OUT &= ~BIT0;
    P1OUT &= ~BIT7;

    user = 0xFE;

    /* Initial values for nRF24L01+ library config variables */
    rf_crc = RF24_EN_CRC | RF24_CRCO; // CRC enabled, 16-bit
    rf_addr_width      = 5;
    rf_speed_power     = RF24_SPEED_1MBPS | RF24_POWER_0DBM;
    rf_channel         = 100;

    init_rudder();
    msprf24_init();
    msprf24_set_pipe_packetsize(0, 32);
    msprf24_open_pipe(0, 1);  // Open pipe#0 with Enhanced ShockBurst

    // Set our RX address
    //addr[0] = 0xDE; addr[1] = 0xAD; addr[2] = 0xBE; addr[3] = 0xEF; addr[4] = 0x00;
    w_rx_addr(0, addr);

    // Receive mode
    if (!(RF24_QUEUE_RXEMPTY & msprf24_queue_state())) {
        flush_rx();
    }
    msprf24_activate_rx();
    void init_rudder();
    //
    //TA0CCR1 = 1500;
    LPM0;
    while (1) {
        if (rf_irq & RF24_IRQ_FLAGGED) {
            msprf24_get_irq_reason();
        }
        if (rf_irq & RF24_IRQ_RX) {
            r_rx_payload(32, buf);
            msprf24_irq_clear(RF24_IRQ_RX);
            user = buf[0];
            if (buf[0] == '0') {
                P1OUT |= BIT0;
                P4OUT &= ~BIT7;
            }   
            if (buf[0] == '1') {
                P1OUT &= ~BIT0;
                P4OUT &= ~BIT7;
                rudder_left();
            }    
            if (buf[0] == '2') {
                P4OUT |= BIT7;
                P1OUT &= ~BIT0;
            }     
            if (buf[0] == '3') {
                P4OUT |= BIT7;
                P1OUT &= ~BIT0;
                rudder_right();
            }        

        } else {
            user = 0xFF;
        }
        LPM0;
    }
}

void init_rudder(void) {
    TA0CTL = TASSEL_2 + MC_1 + TAIE +ID_0;
    TA0CCR0 = 20960; // PWM period 20ms
    TA0CCTL1 = OUTMOD_7; // TA0CCR1 reset/set-high voltage
    TA0CCR1 = 1572;
    P1DIR |= BIT2; // Output on Pin 1.2
    P1SEL |= BIT2; // Pin 1.2 selected as PWM
}

void rudder_left(void) {
    if (TA0CCR1 == 1834) {
        TA0CCR1 = 1572;
    } else {
        TA0CCR1 = 1310;
    }
}


void rudder_right(void) {
    if (TA0CCR1 == 1310) {
        TA0CCR1 = 1572;
    } else {
        TA0CCR1 = 1834;
    }
}

and here is my transmitter code:

#include <msp430.h>
#include "msprf24.h"
#include "nrf_userconfig.h"
#include "stdint.h"

volatile unsigned int user;
unsigned int TXByte;
char buf[32];
void setup_USCI_A1(void);
void main()
{
    char addr[5] = "00005";
    

    WDTCTL = WDTHOLD | WDTPW;

    // Red, Green LED used for status
    P1DIR |=  BIT0;
    P1OUT &= ~BIT0;
    P4DIR |=  BIT7;
    P4OUT &= ~BIT7;
    
    /* Initial values for nRF24L01+ library config variables */
    
    rf_crc = RF24_EN_CRC | RF24_CRCO; // CRC enabled, 16-bit
    rf_addr_width      = 5;
    rf_speed_power     = RF24_SPEED_1MBPS | RF24_POWER_0DBM;
    rf_channel         = 100;

    msprf24_init();  // All RX pipes closed by default
    msprf24_set_pipe_packetsize(0, 32);
    msprf24_open_pipe(0, 1);  // Open pipe#0 with Enhanced ShockBurst enabled for receiving Auto-ACKs

    // Transmit to 'rad01' (0x72 0x61 0x64 0x30 0x31)
    msprf24_standby();
    user = msprf24_current_state();
    //addr[0] = 0xDE; addr[1] = 0xAD; addr[2] = 0xBE; addr[3] = 0xEF; addr[4] = 0x00;
    w_tx_addr(addr);
    w_rx_addr(0, addr);  // Pipe 0 receives auto-ack's, autoacks are sent back to the TX addr so the PTX node
                     // needs to listen to the TX addr on pipe#0 to receive them.
    setup_USCI_A1();
    while(1) {
        while (!(UCA1IFG & UCRXIFG));   // Check if data is available
            char received = UCA1RXBUF;  // Read received byte
            while (!(UCA1IFG & UCTXIFG));  // Wait for TX buffer ready
            UCA1TXBUF = received; // Echo back received byte
        if (received == '0') {
            buf[0] = '0';
        } else if   (received == '1') {
            buf[0] = '1';
        } else if (received == '2') {
            buf[0] = '2';
        } else if (received == '3') {
            buf[0] = '3';
        }
        w_tx_payload(32, buf);
        msprf24_activate_tx();   
        LPM4;
        if (rf_irq & RF24_IRQ_FLAGGED) {
            msprf24_get_irq_reason();
            if (rf_irq & RF24_IRQ_TX){
                P1OUT &= ~BIT0; // Red LED off
                P4OUT |= BIT7;  // Green LED on
            }
            if (rf_irq & RF24_IRQ_TXFAILED){
                P4OUT &= ~BIT7; // Green LED off
                P1OUT |= BIT0;  // Red LED on
            }

            msprf24_irq_clear(rf_irq);
            user = msprf24_get_last_retransmits();
        } 
    }
}

void setup_USCI_A1(void) {
    P1OUT |= BIT0;  // Red LED on
    _delay_cycles(800000);
    P1OUT &= ~BIT0;
    UCA1CTL1 = UCSWRST; //Recommended to place USCI in reset first
    P4SEL |= BIT4 + BIT5;
    UCA1CTL1 |= UCSSEL_2; // Use SMCLK
    UCA1BR0 = 109; // Set baud rate to 9600 with 1.048MHz clock (Data Sheet 36.3.13)
    UCA1BR1 = 0; // Set baud rate to 9600 with 1.048MHz clock
    UCA1MCTL = UCBRS_2; // Modulation UCBRSx = 2
    UCA1CTL1 &= ~UCSWRST; // Initialize USCI state machine
    //UCA1IE |= UCRXIE;
}
/*
#pragma vector=USCI_A1_VECTOR
__interrupt void USCI_A1_ISR(void) {
    __bis_SR_register(GIE);
    P1OUT |= BIT0;  // Red LED on
    _delay_cycles(800000);
    P1OUT &= ~BIT0;
    char received = UCA1RXBUF; // Read received byte
    while (!(UCA1IFG & UCTXIFG)); // Wait for TX buffer ready
    UCA1TXBUF = received; // Echo back
    if (received == '0') {
        buf[0] = '1';
        buf[1] = '0';
    } else {
        buf[0] = '0';
        buf[1] = '1';
    }
    w_tx_payload(32, buf);
    msprf24_activate_tx();   
    LPM4;
    if (rf_irq & RF24_IRQ_FLAGGED) {
        msprf24_get_irq_reason();
        if (rf_irq & RF24_IRQ_TX){
            P1OUT &= ~BIT0; // Red LED off
            P4OUT |= BIT7;  // Green LED on
        }
        if (rf_irq & RF24_IRQ_TXFAILED){
            P4OUT &= ~BIT7; // Green LED off
            P1OUT |= BIT0;  // Red LED on
        }

        msprf24_irq_clear(rf_irq);
        user = msprf24_get_last_retransmits();
    } 
}
*/

Is there a way for me to just pull on the receiver side and not go to sleep?

[LukeVance5]

Partial fix: Switch UCSSEL_2 to UCSSEL_1 (ACLK) for PWM, since my pulse's are very long (ms range) I do not need to use SMCLK. Although I feel like you should still be able to use SMCLK for non receiving purposes