Write programs for two MSP430 boards to do the following:

Board A: If the P1.1 button is pressed, send the message 0xAA via the UART at 9600 baud.
Board B: The red LED shall initially be off. However, if the Board B micro-controller receives a UART message of 0xAA at 9600 baud, turn on the Board B red LED.

Explanation:

#include "msp430g2553.h"

#define TXLED BIT0

#define RXLED BIT6

#define TXD BIT2

#define RXD BIT1

const char string[] = { "Hello World\r\n" };

unsigned int i; //Counter

int main(void)

{

WDTCTL = WDTPW + WDTHOLD; // Stop WDT

DCOCTL = 0; // Select lowest DCOx and MODx settings

BCSCTL1 = CALBC1_1MHZ; // Set DCO

DCOCTL = CALDCO_1MHZ;

P2DIR |= 0xFF; // All P2.x outputs

P2OUT &= 0x00; // All P2.x reset

P1SEL |= RXD + TXD ; // P1.1 = RXD, P1.2=TXD

P1SEL2 |= RXD + TXD ; // P1.1 = RXD, P1.2=TXD

P1DIR |= RXLED + TXLED;

P1OUT &= 0x00;

UCA0CTL1 |= UCSSEL_2; // SMCLK

UCA0BR0 = 0x08; // 1MHz 115200

UCA0BR1 = 0x00; // 1MHz 115200

UCA0MCTL = UCBRS2 + UCBRS0; // Modulation UCBRSx = 5

UCA0CTL1 &= ~UCSWRST; // **Initialize USCI state machine**

UC0IE |= UCA0RXIE; // Enable USCI_A0 RX interrupt

__bis_SR_register(CPUOFF + GIE); // Enter LPM0 w/ int until Byte RXed

while (1)

{ }

}

#pragma vector=USCIAB0TX_VECTOR

__interrupt void USCI0TX_ISR(void)

{

P1OUT |= TXLED;

UCA0TXBUF = string[i++]; // TX next character

if (i == sizeof string - 1) // TX over?

UC0IE &= ~UCA0TXIE; // Disable USCI_A0 TX interrupt

P1OUT &= ~TXLED; }

#pragma vector=USCIAB0RX_VECTOR

__interrupt void USCI0RX_ISR(void)

{

P1OUT |= RXLED;

if (UCA0RXBUF == 'a') // 'a' received?

{

i = 0;

UC0IE |= UCA0TXIE; // Enable USCI_A0 TX interrupt

UCA0TXBUF = string[i++];

}

P1OUT &= ~RXLED;

}

given the options, i would say your best bet is c. the modem supports up to 56 kbps, which is too low for video streaming. dial up modems use actual phone lines, which only can go up to 56 kbps as that's more than sufficient for traditional phone calls. this is also the reason why when a dial-up modem connects, you hear all those sounds. it's literally using the phone line to establish a connection.

which functions return a valid value without any arguments?

(-blank- and -blank- return a valid value without any arguments.)

1st -blank-

today

sqrt

count

2nd -blank-

round

now

sqrt