Well the first thing I fixed was P1DIR was missing BIT4 so I was never outputting a clock so I added that and in the datasheet it also says P1SEL2 should be 0 for BIT4 so I changed that.
Then I added some delays in the setup first since the ADC needs some time for the internal oscillator to start up. The delays in between the different transfers seemed to have helped but I still don't receive what I expect. In the watch window hFA instead of h20, hE9 instead of hA5, hFF instead of h10, and hFF instead of h44.
I hooked up a logic level analyzer I can see that initially both SOMI and SIMO are 255 then SIMO just goes to 192 then 0 and I don't get why.
Thanks,
Noe
#include <msp430g2553.h>
unsigned int Check, Check1, Check2, Check3, Check4; //I put these checks to try and see what was being received
void PinSetup()
{
P1OUT = 0x00; // P1 setup for LED & reset output
P1DIR |= BIT3 + BIT4 + BIT5 + BIT6; // P1 direction as output 1.5 = Reset 1.3=CS 1.6 = Blink LED
P1SEL |= BIT1 + BIT2 + BIT4; // [1.1 = SOMI-> PIN 13 DOUT of ADC] [1.2 = SIMO-> PIN 14 DIN of ADC]
P1SEL2 |= BIT1 + BIT2; // [1.1 = SOMI-> PIN 13 DOUT of ADC] [1.2 = SIMO-> PIN 14 DIN of ADC]
}
void SpiSetup()
{
// UCMSB = Selects Most Sig Fig 1st // UCMST = Select the SPI Module as the Master // UCSYNC = Selecting Synchronous mode
//UCA0CTL0 |= UCMSB + UCMST + UCSYNC; // 3-pin, 8-bit SPI master
UCA0CTL1 |= UCSWRST; // **Put state machine in reset**
UCA0CTL0 |= UCCKPH + UCCKPL + UCMSB + UCMST + UCSYNC;// made ucckpl ->ucckph
UCA0CTL1 &= ~UCSSEL_2; // USCI Clock source will be SMCLK
UCA0BR0 = 0x02; // /2
UCA0BR1 = 0; // Clock divider
UCA0MCTL = 0; // No modulation
UCA0CTL1 &= ~UCSWRST; // **Initialize USCI state machine**set low
}
void SetMaxim() // Trying to set up the ADC registers for clock rate and gain
{
//P1OUT &= ~BIT5; // Pin 1.5 is pulled low to reset ADC
//_delay_cycles(1000000);
P1OUT |= BIT5; // After ADC is reset Pin 1.5 pulled high to prevent reset
//_delay_cycles(500);
P1OUT &= ~BIT3; // Pin 1.3 CS pulled low
//_delay_cycles(500);
//IFG2 &= UCA0TXIFG; // Clear Flag Not sure if I need this????
//while ((UCA0STAT & UCBUSY)); // Transmission Done? Not sure if I need this????
while (!(IFG2 & UCA0TXIFG)); // USCI_A0 TX buffer ready?
UCA0TXBUF = 0x20; // send h20 to tell ADC to be ready to write to clock next
_delay_cycles(50);
Check1 = UCA0RXBUF;
while (!(IFG2 & UCA0TXIFG)); // USCI_A0 TX buffer ready?
UCA0TXBUF = 0xA5; // hA5 for ADC clock run at 2.5Mhz
_delay_cycles(50);
Check2 = UCA0RXBUF;
while (!(IFG2 & UCA0TXIFG)); // USCI_A0 TX buffer ready?
UCA0TXBUF = 0x10; // h10 to tell ADC to be ready to write to the setup reg next
_delay_cycles(50);
Check3 = UCA0RXBUF;
while (!(IFG2 & UCA0TXIFG)); // USCI_A0 TX buffer ready?
UCA0TXBUF = 0x44; // h44 for ADC to setup
_delay_cycles(50);
Check4 = UCA0RXBUF;
P1OUT |= BIT3; // Pull CS high
}
void main(void)
{
WDTCTL = WDTPW + WDTHOLD; // Stop watchdog timer //NV Need from here
PinSetup();
SpiSetup();
SetMaxim();
//__bis_SR_register(LPM0_bits + GIE); // CPU off, enable interrupts
for(;;) // Just threw in this dumy infinite loop for later use
{
_delay_cycles(100000);
P1OUT ^= BIT6; // Toggle green LED (P1.6)
}
}
