Hi.
I am trying to do communication between CCRF and MOD-IO via I2C.
My code is based on TI example for sending multiple bytes as i2c master. (cc430x513x_uscib0_i2c_08.c)
Unfortunately nothing happens when I run it.
Has anyone tried to do something like this?
#include <msp430.h>
unsigned char *PTxData; // Pointer to TX data
unsigned char TXByteCtr;
const unsigned char TxData[] = // Table of data to transmit
{
0x10, // MOD-IO Digital output command
0x01 // Switch relay 1 ON
};
int main(void)
{
WDTCTL = WDTPW + WDTHOLD; // Stop WDT
PMAPPWD = 0x02D52; // Get write-access to port mapping regs
P1MAP3 = PM_UCB0SDA; // Map UCB0SDA output to P1.3
P1MAP2 = PM_UCB0SCL; // Map UCB0SCL output to P1.2
PMAPPWD = 0; // Lock port mapping registers
P1SEL |= BIT2 + BIT3; // Select P1.2 & P1.3 to I2C function
UCB0CTL1 |= UCSWRST; // Enable SW reset
UCB0CTL0 = UCMST + UCMODE_3 + UCSYNC; // I2C Master, synchronous mode
UCB0CTL1 = UCSSEL_2 + UCSWRST; // Use SMCLK, keep SW reset
UCB0BR0 = 12; // fSCL = SMCLK/12 = ~100kHz
UCB0BR1 = 0;
UCB0I2CSA = 0x58; // Slave Address is 048h
UCB0CTL1 &= ~UCSWRST; // Clear SW reset, resume operation
UCB0IE |= UCTXIE; // Enable TX interrupt
while (1)
{
__delay_cycles(50); // Delay required between transaction
PTxData = (unsigned char *)TxData; // TX array start address
// Place breakpoint here to see each
// transmit operation.
TXByteCtr = sizeof TxData; // Load TX byte counter
UCB0CTL1 |= UCTR + UCTXSTT; // I2C TX, start condition
__bis_SR_register(LPM0_bits + GIE); // Enter LPM0, enable interrupts
__no_operation(); // Remain in LPM0 until all data
// is TX'd
while (UCB0CTL1 & UCTXSTP); // Ensure stop condition got sent
}
}
//------------------------------------------------------------------------------
// The USCIAB0TX_ISR is structured such that it can be used to transmit any
// number of bytes by pre-loading TXByteCtr with the byte count. Also, TXData
// points to the next byte to transmit.
//------------------------------------------------------------------------------
#pragma vector = USCI_B0_VECTOR
__interrupt void USCI_B0_ISR(void)
{
switch(__even_in_range(UCB0IV,12))
{
case 0: break; // Vector 0: No interrupts
case 2: break; // Vector 2: ALIFG
case 4: break; // Vector 4: NACKIFG
case 6: break; // Vector 6: STTIFG
case 8: break; // Vector 8: STPIFG
case 10: break; // Vector 10: RXIFG
case 12: // Vector 12: TXIFG
if (TXByteCtr) // Check TX byte counter
{
UCB0TXBUF = *PTxData++; // Load TX buffer
TXByteCtr--; // Decrement TX byte counter
}
else
{
UCB0CTL1 |= UCTXSTP; // I2C stop condition
UCB0IFG &= ~UCTXIFG; // Clear USCI_B0 TX int flag
__bic_SR_register_on_exit(LPM0_bits); // Exit LPM0
}
default: break;
}
}
The first problem is that according to schematics the MODIO UEXT and CCRF UEXT are not compatible.
MODIO has SCL/SDA on pins 3,6 and CCRF has SCL/SDA on pins 5/6... strange... So you can not connect the 2 with the standard UEXT cable.
The UEXT SDA signal on female connector on MODIO has a 4.7K pullup resistor while on there is none on the male connector. Both SCL & SDA on CCRF have 4.7 pullup resistors.
So I used male connector on the MODIO side. I connected GNDs on PIN 2, SDAs on PIN 6 and SCL pin 3 on MODIO to SCL pin 5 on CCRF.
But still nothing.
Hey Zeronio,
The SCL/SDA are on the same UEXT pins 5-6. The problem is in the .pdf export from the eagle source file that shifted the entire column up by one position.
Best regards,
Lub/OLIMEX